I expect the US population that cares about torrents is practially nil, though that is based personal bias.

If that population is practically nil, then what's the problem with torrents/pirating?

Nobody doing it: no loss to the studios.

Even without knowing exactly, precisely how many people int he USA are torrenting and pirating, the studios seem to think it's a Great Big Deal, and are willing to splash out a lot of cash, and a lot of good will to get torrenting stopped. That would seem to indicate that the US population that cares about torrents is actually pretty large.

Which side, people bringing entertainment to them or the ones destroying any private life they have left?

People bringing entertainment to them or the ones who don't hesitate to literally destroy someone's life over a bunch of copied pop songs or movies?

Truth be told, it really depends on which side has more control over the narrative in the media.