I Don't Get It

http://www.sfgate.com/cgi-bin/article.cgi?f=/n/a/2008/06/19/politics/p060323D99.DTL

Why is it even mildly scandalous that Barack Obama said that he’d take public money and then decided not to? Are there restrictions attached to the Presidential Campaign Fund that he doesn’t have to abide? Or is it just that it theoretically looks bad for the other candidate to have his hand in the public cookie jar while he doesn’t?