With the exception of Red Sox vs. Yankees games and postseason games, there were plenty of empty seats at the Red Sox games I attended last year at Fenway Park during the regular season. The poor performance of the team in 2012 probably had a lot to do with lackluster attendance, but I also wonder how much of that was due to ticket prices. Looking at the ticket pricing for this season, I wouldn't be surprised to see the same thing happen this year even with the 2013 World Series Championship title.
Single game ticket prices...
Red Sox Ticket Pricing | redsox.com: Tickets
Single game 'Green Monster' seating prices...
Red Sox Ticket Pricing | redsox.com: Tickets