I am hurting my ISP, but there are 5 other guys that are not, that subsidize me, and therefore the ISP still makes a profit.
Of course not everyone is going to consume the same amount of data.
It's like the fat guy at the buffet eating 3 plates. Sure he might be costing the restaurant money for his plate, but for every fat guy there are 5 other people that don't eat as much.
In the end everyone still gets to eat how much they want to and the restaurant makes a profit.
If buffets/uncapped aren't making their target, then why are they still offering it?
It's because they make money.
Some of us consume too much, but most of us don't. It balances out - I don't see a problem.