I found a way in a listing-price.php (added comment in code //manually added), which I hacked a bit, but now I have slight problems 
1. I'm using simplified registration method, so when user register he automatically log in. This "hack" is not applied in that moment, user needs to log out and log in again for these changes to be visible. Hmmm?!?!
2. From all modules prices somehow dissapear..I guess that is not so normal behavior 
p.s.
I'm using 3pd plugin, so I can choose Joomla user group within HikaShop registration. Also my Joomla usergroup have ID = 9.
<?php
/**
 * @package		HikaShop for Joomla!
 * @version		1.5.6
 * @author		hikashop.com
 * @copyright	(C) 2010-2012 HIKARI SOFTWARE. All rights reserved.
 * @license		GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html
 */
defined('_JEXEC') or die('Restricted access');
?>
<span class="hikashop_product_price_full">
    <?php
    if (empty($this->row->prices)) {
        echo JText::_('FREE_PRICE');
    } else {
        $first = true;
        echo JText::_('PRICE_BEGINNING');
        $i = 0;
        foreach ($this->row->prices as $price) {
            if ($first)
                $first = false;
            else
                echo JText::_('PRICE_SEPARATOR');
            if (isset($price->price_min_quantity) && empty($this->cart_product_price) && $price->price_min_quantity > 1) {
                echo '<span class="hikashop_product_price_with_min_qty hikashop_product_price_for_at_least_' . $price->price_min_quantity . '">';
            }
            $classes = array('hikashop_product_price hikashop_product_price_' . $i); 
            if (!empty($this->row->discount)) {
                $classes[] = 'hikashop_product_price_with_discount';
            }
            $user = & JFactory::getUser(); //manually added
            if ((in_array('9', $user->groups)) && ($i == 0) && (isset($_GET['cid']))) { //manually added
                echo ''; //manually added
            }else{ //manually added
                echo '<span class="' . implode(' ', $classes) . '">';
                if ($this->params->get('price_with_tax')) {
                    echo $this->currencyHelper->format($price->price_value_with_tax, $price->price_currency_id);
                }
                if ($this->params->get('price_with_tax') == 2) {
                    echo JText::_('PRICE_BEFORE_TAX');
                }
                if ($this->params->get('price_with_tax') == 2 || !$this->params->get('price_with_tax')) {
                    echo $this->currencyHelper->format($price->price_value, $price->price_currency_id);
                }
                if ($this->params->get('price_with_tax') == 2) {
                    echo JText::_('PRICE_AFTER_TAX');
                }
                if ($this->params->get('show_original_price') && !empty($price->price_orig_value)) {
                    echo JText::_('PRICE_BEFORE_ORIG');
                    if ($this->params->get('price_with_tax')) {
                        echo $this->currencyHelper->format($price->price_orig_value_with_tax, $price->price_orig_currency_id);
                    }
                    if ($this->params->get('price_with_tax') == 2) {
                        echo JText::_('PRICE_BEFORE_TAX');
                    }
                    if ($this->params->get('price_with_tax') == 2 || !$this->params->get('price_with_tax')) {
                        echo $this->currencyHelper->format($price->price_orig_value, $price->price_orig_currency_id);
                    }
                    if ($this->params->get('price_with_tax') == 2) {
                        echo JText::_('PRICE_AFTER_TAX');
                    }
                    echo JText::_('PRICE_AFTER_ORIG');
                }
                echo '</span> ';
                if (!empty($this->row->discount)) {
                    if ($this->params->get('show_discount') == 1) {
                        echo '<span class="hikashop_product_discount">' . JText::_('PRICE_DISCOUNT_START');
                        if (bccomp($this->row->discount->discount_flat_amount, 0, 5) !== 0) {
                            echo $this->currencyHelper->format(-1 * $this->row->discount->discount_flat_amount, $price->price_currency_id);
                        } elseif (bccomp($this->row->discount->discount_percent_amount, 0, 5) !== 0) {
                            echo -1 * $this->row->discount->discount_percent_amount . '%';
                        }
                        echo JText::_('PRICE_DISCOUNT_END') . '</span>';
                    } elseif ($this->params->get('show_discount') == 2) {
                        echo '<span class="hikashop_product_price_before_discount">' . JText::_('PRICE_DISCOUNT_START');
                        if ($this->params->get('price_with_tax')) {
                            echo $this->currencyHelper->format($price->price_value_without_discount_with_tax, $price->price_currency_id);
                        }
                        if ($this->params->get('price_with_tax') == 2) {
                            echo JText::_('PRICE_BEFORE_TAX');
                        }
                        if ($this->params->get('price_with_tax') == 2 || !$this->params->get('price_with_tax')) {
                            echo $this->currencyHelper->format($price->price_value_without_discount, $price->price_currency_id);
                        }
                        if ($this->params->get('price_with_tax') == 2) {
                            echo JText::_('PRICE_AFTER_TAX');
                        }
                        if ($this->params->get('show_original_price') && !empty($price->price_orig_value_without_discount_with_tax)) {
                            echo JText::_('PRICE_BEFORE_ORIG');
                            if ($this->params->get('price_with_tax')) {
                                echo $this->currencyHelper->format($price->price_orig_value_without_discount_with_tax, $price->price_orig_currency_id);
                            }
                            if ($this->params->get('price_with_tax') == 2) {
                                echo JText::_('PRICE_BEFORE_TAX');
                            }
                            if ($this->params->get('price_with_tax') == 2 || !$this->params->get('price_with_tax') && !empty($price->price_orig_value_without_discount)) {
                                echo $this->currencyHelper->format($price->price_orig_value_without_discount, $price->price_orig_currency_id);
                            }
                            if ($this->params->get('price_with_tax') == 2) {
                                echo JText::_('PRICE_AFTER_TAX');
                            }
                            echo JText::_('PRICE_AFTER_ORIG');
                        }
                        echo JText::_('PRICE_DISCOUNT_END') . '</span>';
                    } elseif ($this->params->get('show_discount') == 3) {
                        
                    }
                }
                if (isset($price->price_min_quantity) && empty($this->cart_product_price)) {
                    if ($price->price_min_quantity > 1) {
                        echo JText::sprintf('PER_UNIT_AT_LEAST_X_BOUGHT', $price->price_min_quantity);
                    } else {
                        echo JText::_('PER_UNIT');
                    }
                }
                if ($this->params->get('show_price_weight')) {
                    if (!empty($this->element->product_id) && isset($this->row->product_weight) && bccomp($this->row->product_weight, 0, 3)) {
                        echo JText::_('PRICE_SEPARATOR') . '<span class="hikashop_product_price_per_weight_unit">';
                        if ($this->params->get('price_with_tax')) {
                            $weight_price = $price->price_value_with_tax / $this->row->product_weight;
                            echo $this->currencyHelper->format($weight_price, $price->price_currency_id) . ' / ' . JText::_($this->row->product_weight_unit);
                        }
                        if ($this->params->get('price_with_tax') == 2) {
                            echo JText::_('PRICE_BEFORE_TAX');
                        }
                        if ($this->params->get('price_with_tax') == 2 || !$this->params->get('price_with_tax')) {
                            $weight_price = $price->price_value / $this->row->product_weight;
                            echo $this->currencyHelper->format($weight_price, $price->price_currency_id) . ' / ' . JText::_($this->row->product_weight_unit);
                        }
                        if ($this->params->get('price_with_tax') == 2) {
                            echo JText::_('PRICE_AFTER_TAX');
                        }
                        echo '</span>';
                    }
                }
                if (isset($price->price_min_quantity) && empty($this->cart_product_price) && $price->price_min_quantity > 1) {
                    echo '</span>';
                }
            }//manually added
            $i++;
        }
        echo JText::_('PRICE_END');
    }
    ?></span>