Is the only thing that separates gambling from the stock market the fact that stocks provide ownership?

I'm not talking retirement or long term holdings, but more day trading where you close out all positions by days end. Isn't it essentially a bet that the stock will move up or down? Up you make money, down you lose, (long positions only). How is that different from a gamble? But please spare the fundamental differences between stocks and sports bets, I'm talking of a boiled down version. If you bet a stock will go up and it does, how is that different from a sports bet? Aren't they both "gambles" that the unkown will work in their favor? If so, is the only difference the fact that stock represents ownership? Now that i think of it, lets talk options too. An option itself isn't ownership itself but the opportunity to buy ownership. So if an option is closed out and not exercised, isn't that a bet? Oh and by the way, i'm looking for specific LEGALITY, not if you think so or not. Thanks in advance.