Hi,
Yes and no. The goal of a link custom field is to provide a text and a URL so that the field can display it as a link.
So, if you only use it to provide a URL, the system doesn't work properly as it is not meant to be used that way.
In that case, you could use a "text" field to provide the URL, and you could the "format" setting to make it into a link if necessary for the frontend display.
Now, following your message, I've worked on this so that the field behave properly when using it only with a URL. I've added the patch for that on our end.
So, if you download the install package of HikaShop on our website and install it on yours, you'll get the patch and it will work properly with your use case.