If you use Ebay labels, when you go to print the label there is a blurb at the top of the page, in an orange or yellow box, that reads in essence that the item has not been paid for and to not ship. It's pretty hard to overlook.
But yes, it would be very helpful, and actually make a lot of sense, for that link to not appear until a payment had actually been made.
The easier you are to offend the easier you are to control.
We seem to be getting closer and closer to a situation where nobody is responsible for what they did but we are all responsible for what somebody else did. - Thomas Sowell
