"It's not that much to ask i would have thought."

No, it's not too much at all. On the contrary, not doing it is what seems rather clueless - unless there is some arcane marketing motive. I can see vendors maybe not realizing it but I would think the store would be all for enhancing the shopping experience. I would go with a roll-over so as not to clutter up the item name, but that's it. The whole idea of selling something should be to make the process as easy as possible, not to prove some sort of work ethic by jumping through unnecessary hoops. Some people are still on dial-up. Who wants to be loading extra pages though, when it isn't necessary, no matter how fast your connection.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken