I think Chael fears not being given his due (or what he perceives to be his due). There was an interview from a year ago or so when Chael plainly spoke about the reason for his transition from a soft-spoken guy who fought Filho and Maia to the raving hype monster that was on his way to almost singlehandedly selling some of the biggest fights in the history of the sport.
According to Chael (here's the source: http://sportsillustrated.cnn.com/201...nen/index.html
), he contacted Joe Silva, offering to fill in on short notice (at LHW!) back in 2009, and Joe Silva texted back "Who is this?" (meaning he didn't have Chael's number saved in his phone despite the fact that Chael just fought Maia and was scheduled to fight Okami). From that point on, Chael realized what he had to do to get ahead and stay ahead - and that is shameless self-promotion.