The problem with the stock market isn't that you might lose money, the problem is that share prices are largely driven by perception rather than substance. At the extremes it makes sense, in that a company that runs out of money is worthless and a company that makes 14bn profit a quarter is worth something. For the rest it is like popular culture / fashion.

The other problem with stocks is that if everyone is saving for the future via retirement funds then the market is inherently going to be over inflated and further illogical.