Actually Sierra/Vivendi used to do this on most if not all of its titles with the first 30 days of purchase AND provide a return shipping refund. [...] Microsoft also had a 30-day money back guarantee on at least some of its PC games. Links 2001 was one. Today though I can't think of any publishers which do that off the top of my head.
Possibly because most games nowadays can be finished over a weekend or two?