The fact that cryptocurrency is brand new and still growing like mad leads to the situation that there is no concensus yet on how to value a coin. It is not similar to a stock (no dividend) but of course some you can develop some thoughts or projections on the end value of cryptocurrency. For now, everyone sees it as limitless.
Once the market matures (at much higher prices), we will see it getting stable, dull and boring with only the few surviving coins/applications as the big winners. So we are on our way to find the 'Intel Corporation' and the 'x86 instruction set' among cryptocurrencies. It may not have been invented yet.
Yes you are correct but I was comparing it to the stock market not a stock. The market is so new that we have no way of telling whether these new coins are overvalued or not. This indirectly means that if there is one major mistake it could cause a freak out sell and kill the market in the short term.
However, long term I am very excited and yes we are waiting for the Intel Corporations to come along. Although I think one may be on the horizon. I'm putting my money on EOS.