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

There are many gambling sites that offering investment from their bankroll, I think the words "high risk investment" is if you directly invest in the gambling site but if you only play then the words "high risk investment" is not right, just like other said gambling is only game that we have play with money involve.