I never realized just how bad this can be until I started selling/marketing my startup. I was so confused by the reaction to my participation on a few subreddits where my target customers hang out - I had never experienced anything like it before.

I started to see patterns (not only against my posts personally, although I quickly stopped trying to participate) because I began to understand the market players. It's unreal how inauthentic most of the content actually is and how much of it is straight up shill marketing. I suspect this is true for a large number of niche forums where specific products or services become "blessed" by the community.

The only way to accomplish this is with either a large network of puppet accounts or with the support of the moderators. Probably both.