The ads (and it's been debated) is (imho as well) a way to 'buy out those who can keep then in check'. Media/journalists are supposed to be doing that. But when your chief editor tells you "hey, 70% of our network's revenue comes from XYZ" even if you don't want to, you self-censor.

Anyway I have commented many times on the 'legalized bribing' called 'lobbying'. The dishonest ones always week because those with $$$ know very well who can they buy and who can they threaten.