You act like they all act rationally with maximum information.

Kids are growing up with the culture of sports betting, meme stocks, Robinhood for easy investing (even if you can’t afford a single share of a stock), virtual items and loot boxes, “blind box” products, etc. the entire economy runs on taking advantage of people with gambling compulsions / addictions.

And to answer your rhetorical-but-not-really question, not all people know they are “the fish” (referring to the quote from the movie Rounders).

Because the way these companies make money is incentivizing the behavior of gambling addicts. It's just like asking why people will continue taking drugs if it's known to harm them.