It seems to me that Amazon has the same problem, but with their physical products instead of ads. Cheap junk, fakes, and scams pushed up sales for a while, but

It seems to me that Amazon has the same problem, but with their physical products instead of ads. Cheap junk, fakes, and scams pushed up sales for a while, but then people give up on the site and go to other sources that are perceived to be more reputable.