[jefftk]

> this has only negative effects like less competition because the large player dominate trough ads

Ads can also be good for competition: if your upstart product is better or cheaper ads can help you get the word out. Here's a paper that looks at the effect of advertising bans on eyeglasses, and sees that they led to higher prices: https://www.jefftk.com/benham2013.pdf

(Disclosure: I work in ads)