eBay will never appeal to everyone because it involves patience and a bit of work on the part of the buyer. If you're not willing to put in this effort, you may as well pay a "little more" to an online shop or LBS. I have had ~1600 transactions since I opened my account in '07. And typically pay dimes on the dollar for the things a buy. Cycling and otherwise.
As said, it's not for everyone. But I get tired of the mantra "you get what you pay for". Your getting what you're paying, in my opinion, way too much for. Cycling, like many diversions, is often an obsession, and prices reflect that.
As both a both a buyer and seller, I realize that eBay is definitely weighted in favor of the buyer. There's a lot more accountability for eBay sellers than other retailers. Just look at threads over on the WW forums from buyers that made purchases from Ciamillo than received nothing than empty promises. They had to file CC claims that take months to resolve. If those purchases been made on eBay, the refund would have taken a couple of weeks.