I don't have an opinion either way on that, but I do have a ton of information that everyone here will be interested in.

The manipulation of social media is typically referred to as "astroturfing." PR firms and governments hire people to push fake grass-roots campaigns, hence the term. See the Astroturfing Information Megathread, which is a continuously-updated archive of links with information on corporate and government astroturfing.

I believe Reddit is a primary target for a few reasons. Reddit.com is the 7th most popular website in the United States (3rd largest for social media) and has more traffic than mainstream media and media websites, such as cnn.com. This is the best website to spread information using minimal effort. You don't need followers or anything else. Just make an account and post. Some marketers do decide to purchase old, high-karma accounts to seem legit, but these cost between 50 and 70 bucks for a decent one. To give you an idea of how small that amount of money is, here is a low-level shill who boasted about making 27,000 dollars in sales from using a couple accounts and posting pics to Reddit. Imagine the amount of money corporate marketers rake in using this site.