The guy's running a business. He has a responsibility to his shareholders to make it as valuable as he can. Sticky apps/web sites lead to more ad impressions and higher prices. His business does not give people cancer or HIV.
You may find life more rewarding to assume people are good and try to see the best in people. As Dale Carnegie says in How to Win Friends and Influence People, if you assume the best in people and encourage them, they're more likely to want to live up to that image.
Capitalism's an economic system, not a moral one. He's got his responsibility to make money at any cost. Civic society has its responsibility to draw a line past which the cost is too high. History makes it clear that "assuming the best" about the actions of the rich and powerful hardly keeps them accountable.
You may find life more rewarding to assume people are good and try to see the best in people. As Dale Carnegie says in How to Win Friends and Influence People, if you assume the best in people and encourage them, they're more likely to want to live up to that image.