Kind of odd to even bring ethics up when discussing how websites make money. It doesn't matter at all.
This is why we can't have nice things. Because people adopt a FYGM attitude. Because they piss in the pool we all have to swim in.
...all that harm can be removed simply by...
...quitting smoking? Throwing away the prescription pain meds? Giving up junk food?
How about not robbing people of their valuable time and money? How about moving past negative-sum business models where the distributed costs far outweigh the concentrated gains?