Of course they work and they're often both very effective and profitable. Half of the time I'm not even aware of 99% of these crapcoin ICOs until I see them advertised here by shitposters crapping all over the place; so yes, they're very effective. Also, often it doesn't cost them very much if anything at all. Most are paid out via tokens they've pre-mined themselves so there's no real cost to them. If you don't hire a campaign manager - which many don't - then there's no real loss at all. Many make sufficient money via their crowdsale so it's worth paying one anyway. The shameful thing is that it's counterproductive to them to have a manager who does his job because the more people posting = the more people who see their advert so it doesn't really matter about quality of posts either. This is something that should change though and they shouldn't be allowed to operate here in such a way.