I'm not sure you understand how poker works. It is not negative expectation gambling like all casino games. A skillful player has a positive expectation over time, and will be profitable.
You're playing against other people, not against the casino. So, yes, some people will lose their money, but the more skillful players will win it.
As someone who spent about 18 months building a No Limit Hold'em bot, I can safely tell you that the "bot problem" is not as big of a problem as it might seem like it would be.
Not only do you have to program a winning strategy--which is very hard--but you have to not get caught--which is also very hard.
Both 'very hard' problems seem best solvable by a tiny bit of collusion with the site operators: run the bots as shills, disproportionately pair them against weak-player-heavy tables, drag just a little on enforcement of bot-detection mechanisms.
I know, I know: "if the operator is dishonest there are easier ways to cheat". But this looser collaboration between bot-operators and site-operators is easier to disguise, or to compartmentalize. It doesn't require dishonest software, for example.
It might even be easier for perpetrators to rationalize. ("These players are dumping their money anyway; it might as well be to my confederates' bots. Bot-training is a skill, too!")
I'm fully aware of how poker works, and the majority of people playing the game lose money.
You've got a distinct minority of people (I'd guess < 10%) who win the money from the stupid poker players. Since I am one of those stupid people I've decided not to pay the incomes of the advanced and more skillful poker players.
SharkScope, which tracks the results of all the major poker sites' Sit-n-Gos--which are basically short tournaments--says about a third--33%--are winners.
That doesn't include cash games, which probably has a lower win rate than 33%, but likely not as low as 10%.
You're playing against other people, not against the casino. So, yes, some people will lose their money, but the more skillful players will win it.