There are good and bad points to almost everything. There are some scam artists on every corner. Ebay just has several corners. The good part about ebay is folded up in the idea of access. You can get stuff that you couldn't buy elsewhere. You can sell stuff that you wouldn't have been able to sell somewhere else. I live in a smaller town and cannot affor to drive 60 miles to get some little piece or part that I needed. When I was rebuilding my fa50, I saved a bundle from having to go through the dealer.
Books that you cannot even find in the large book stores. Antiques and NOS parts that would have been worthless can now be obtained at generally fair prices. I still go with what I am willing to pay for an item. I also look at the feedback of the seller and the other bidders if it is a high priced item. I've bought and sold stuff that you just cannot find on the east coast and have seen things that would have had to go to a pawn shop at a horrible loss be sold on Ebay.
You can buy and sell to people you will never meet. Things that might have clogged up the land fills have been made useful because of Ebay. Personal belongings being sold on Ebay have made owning certain items a reality for individuals that could not have afforded certain products. From older computer components to the $75 dollar camera that would have brought 10 at the pawn shop. Ebay has made it possible to extend your yard sale across the country.
If you want to get pissed at someone, go into a pawn shop. Usery at it's best. Those folks get some major profit off of others misfortune.