Many ICOs are definitely cash grabs! Buzz words and good promotion still gets them a shitload of ETH/BTC despite very little fundamentals because investors speculate on big returns once the tokens hit the exchanges! As long as this works out for the investors, the ICO madness will go on and this will definitely continue to destabilize the market. To answer your question, yes many ICOs create value out of thin air as they will die out in the long run and we should definitely be worried about that!