There is a market for the ads, they will just move somewhere else. Politicians think you can order something to be stopped, and consumers will adjust their needs and wants out of fear of fines or imprisonment.
It never works. People still snort coke, hire hookers and dog fight. The great thing about the internet is that it exists above all legal jurisdictions. Anarcho-capitalism.
The upside of this, is that while the market may shrink a little, it should become more (competitive) profitable per action.