I think it's because people expect everything on ebay to be a "Bargin" so therefore expect evreyone selling on there are going to be giving whatever it is there selling away...

I've got my car on there at the mo and to be honest I really wish I hadn't bothered, it was pulled twice by eBay as I had broken the rules with the wording in the Ad, and i've had people asking all the questions under the sun people askin if they can view and not getting back too me and of course the fukkin stupid offers.

I'll probably end up selling it privately and will have wasted the money listing it on ebay