So which of those games were especially shitty? Have you even played any of them? There are probably bad ones, but I have played a few that were pretty good. The best thing about them was that they did something that an AAA title would never do: dare to try something new. It wasn't always in the gameplay (Faster Than Light), sometimes it's just the mood of the game (Limbo), an unusual setting (The Binding of Isaac), the story that is told (To the moon), but sometimes, it's everything (Braid).
And seriously, if you ever have two dollars to spare, and Intrusion 2 is 75% off, you should try it. It's one of those 8bit platformers, but it's great. Short, but intense.
I agree that they are mostly overpriced, though. Not ready to shell out close to 20 dollars for a game that lasts for 5 hours. But a few dollars for a 5h break from the commercially streamlined standardware is a good deal IMO.