The problem of Ebay isnt not accepting bitcoin but their high fees, if they accept bitcoin and keep with their high fees it wont change anything, besides the fact to bitcoin start to become more famous. This is something they must take care, since bitcoins are connected to low fees, ebay should reduce their fees if they would work with bitcoin, otherwise we would see the complaints raising a lot.
EBay makes money on those fees, and it's part of the reason why they are able to maintain their website and services in the same way that they do right now. As much as everyone would love to have those fees lower, the company still has to be a money-maker for the shareholders, and if they can't do that, everyone loses out on the service.
It sucks how that works, but that's just how it is. It can't be fixed easily.