you are so wrong and probably you aren't an investor yourself
in the short term you will only win or lose small fractions , which doesn't worth the try
but investing in gambling when you have a small edge will make you money only in the long run , cause there is much variance
for me I only consider my yearly results when it comes to investing in gambling sites , and it's better than leaving my coins in a wallet
You are also wrong. In the short term you can win or lose big, due to variance - so it's not simply that it's not worth the effort, it's just not likely to be worth the effort. In the long run, however, your profit will correlate with the house edge of the casino in question
Well, in short term anything can happen, you can get big or small profit or big/small loss, but it's all about the long run, where you expect to see profit. As for risks, it's better to look on bankroll size, max allowed win, as well as reputation of the house and some other factors of their business.