Did you ever buy something but never use it?
If you’re a taxpayer in Florida, you have — it’s called the upper deck of Marlins Park. The club is upgrading all upper-deck ticket holders to the lower levels, because attendance is so bad (I found this story through the excellent baseball newsletter The Slurve). But, of course, the stadium received about $600 million in corporate welfare.
[Related article from 2010: "The Florida Marlins are Stealing Your Money."
Update: John McCain has introduced legislation to bar teams from blacking out TV coverage for games that don't sell out if they received public funding for their stadiums.]