Yeah, it's true. I should know, I can be a PITA too for sellers who won't take the time write out a description of a game's cosmetic condition and completeness. I try to make the complaint and subsequent return as painless as possible, but I'm not gonna just take it if a game is listed as "very good" when it has rips, creases, fading, scratches, etc, and I end up buying it on good faith of the condition they listed and the shoddy photos taken that obscured the issues.
It goes both ways, is what I'm saying. Sellers don't try hard enough, and buyers expect a lot. I expect sellers to know they're dealing with potential collectors who will be particular, and that it's not a good idea to dress up something as better than it actually is to boost the sale.
As a seller, I've had no complaints. I make sure the photos are representative of the item, and I describe anything noteworthy about their condition or completeness. I also list for lower than the other guys, especially if it's not that good. I've had nothing but happy customers there.
Also, it's entirely possible that people might not receive an item that was marked as delivered. It's happen to me before. My package was simply delivered to the wrong address, and so whoever that person was, they kept my package and I simply had to take a loss. That should be on the post-office, but they won't take responsibility for anything. Signature confirmation should be available on request, but no one uses it.