My understanding about the advertising ecosystem on Reddit is such that the returns on the actual advertising platform are far, far worse than grassroots marketing (not even talking about sneaky stuff -- participating in the community, doing AMAs, generally just hanging around).
There are reddit admins who poison reddit ads, because they can freely place ads on subreddits without cost. It's annoying.
The reddit ads system could be far better and without the corruption. It does cost more and is less effective than Facebook ads even for very specific subreddits, and it costs a ton more than it's worth even when there is no one else buying ad space in a subreddit.
I've run a few adverts on Reddit and the returns were far better than Adsense, we got a lot of long-time customers through Reddit and plenty of clicks.
I really like the fact you can comment on the adverts as if they were a post, this lets people discuss (and hopefully praise) your company.
