I'm just going to tell a little story here.
A long time ago, I worked on a recolorable Drupal theme, which was to be the new default look (Garland). It was completed and awaiting the next major release. Before that happened though, Matt Mullenweg grabbed the theme and the assets from our repo, ported it to Wordpress, and offered it as a theme on wp dot com to his customers.
When this was pointed out as being in extremely poor taste, he hid behind the GPL as the justification. WP was large enough already at the time that they could get away with stuff like this without suffering too much PR damage.
In short, if he's bragging about how much money he's making, it's because he has few scruples and doesn't actually care about credit and respect.