The opposite is also true; some of them have no unique features and nothing behind them in terms or development or merchant adoption. Most are just clones and get rich quick schemes. Some will survive; some wont; some will become useful and of worth; others wont. It'll be interesting to see what other alt coins merchants start accepting.
I agree with you. Most of alt-coins don't have any credibility and no chance for adoption, it's just matter of time when they die.