Some companies (like gaming companies) "sponsor" a subreddit and give out prizes and benefits in small contests and whatnot. Those subreddits employ moderators who will delete, alter or chastise any negative content relating to that company and ban anything but positive reinforcement of that company.
cough Stadia cough - it is against Reddit ToS that employees (or at least reddiquette) to have a paid employee of a company moderating a subreddit for that company's product [1].
