Gambling.

It`s free and gives you lots of things to grind for... if you have restraint not to spend money on it.
Also the newer gacha games are actually better then the AAA garbage released recently.
Of course there are good ones that can be decent free-to-play and absolute garbage ones that are only there to squeeze your wallet dry by every mean possible.

Purtty girls.

Why does anybody like anything?

Gambling and gooning are a golden combo. They know that there's a lot of guys who would rather be buying the chance to win a skin to goon to than to buy a date dinner for the gamble of will they lose their virginity.

You answered your own question, TC.

Unless it's based on an RPG series or something. Then they don't like it, but they get trapped in it.

People join for huge knockers and 30 min in cry their eyes off at some Nier: Automata level ♥♥♥♥.

Mental illness that amplifies their addictive personality traits.

Plus ignorance or apathy towards the fact that that's being preyed upon.

Because I like softcore porn.

quick dopamine