They don't, honestly this stuff goes to the top and its been this way for a long long time. Any niche interest subreddit that has gear or products has a sidebar with some stuff that's ordained by the moderation team to be "The best X for Y" and therefore incessantly recommended in the comments and all over the subreddit. Sometimes you will even see metathreads where the users are complaining about the recommendations listed in the subreddit's official wiki or faq page.