I put a lot of money into advertising through the "proper channels" for my business, including Facebook Ads. We were crushed by a competitor who activated a few links within his PBN and spent some serious time astroturfing, both tactics that I had refused to engage in.

The sad reality of online marketing is that people who are buying ads are suckers. The only way to be competitive online is to actively game the mechanisms that the few big traffic brokers use to determine rank.