The same reason you don't pirate photoshop.
Adobe don't mind. You wouldn't buy it anyway. What suffers is the cheaper/free competition that is completely starved.
Surely you realize that avoiding disrespectful sites and seeking proper sites will send a message?
Two actually, one that that kind of shit isn't acceptable and second, that you appreciate honest people.
If you can't be bothered then maybe we actually deserve the cesspool we've created.
It takes a few minutes to set up pi-hole, and it isn't just for websites either. It happily swallows in-app advertisements. The benefits are extended to anybody on your wifi. What possible reason would you have to not use it?