It only works if you sell a hugely priced item/service.

If you want to sell everyday consumption or end consumers items, this scheme will eat all your income/benefit.

After reading about all the flaws in automatic online advertising through clicks on this thread, it looks like a big scam prospering more or less in favor of opacity, lack of fine tuning or targeting and fraud.

Referral systems and social influencers seems to be a better option, as long as your product is good and would not shame the ones endorsing it. Betting on viral marketing and endorsement seems to be more natural and a better bet, but require maybe more work and preparation than blind automatic system.