It's sad that samsung would do this... Is it commonplace for companies to do this?
Even the small/local businesses do this. Just check Yelp reviews. Hell, Yelp used to allow businesses to move their best reviews to the top if they paid them enough.
1) http://www.eastbayexpress.com/oakland/yelp-and-the-business-...
2) http://www.zdnet.com/blog/apple/the-yelp-mafia/3116
3) http://arstechnica.com/tech-policy/2010/02/yelp-facing-class...
There was so much fallout from this back in 2009/2010 that Yelp had to turn the tables and pretend to play nice guy finally by outing businesses that buy positive reviews (starting last October).