I know it isn't an investment, but in the last few years some "high risk" investment funds have appeared, and in them you can either lose it all or earn a lot of money.
Isn't this basically the same as gambling? Wouldn't it be faster to just deposit the amount in a casino? At least you'd be able to spend your earnings much sooner

You can see it like that because with gambling you are putting money on a game where you do not know the outcome of and the fact that you have a bigger chance of losing is a high risk that you take.
The only thing is that you are not really investing in it but the casino is just taking your money.