Because ICSTOR is one of the devs who doesn't really care if his game gets leaked, he still has shit tons of subscribers and gets more than enough money. Why would he even care at this point anymore? Now for example let's look other, even bigger developer studio, Inceton Games. They care about their products enough (unlike ICSTOR) that they are actively going after the pirates and pirated links on the internet, they have even hired proper DMCA agency to try to take most of the illegal versions down from the different sites. So if Patreon devs would want, they could get the links down from pirate sites. But for most of the devs, the pirate sites are free advertisement and they understand that the free advertisement means most likely more supporters to their Patreon or SubscribeStar, which then means more money.