Or, did the MAME team change the license after developers contributed to the code base in good faith, in order to sell the package to Google? If that's the case then they are evil cunts.
this. lots of devs submitted code under old license. mame dev team just relicensed stuff unilaterally, and stripped licenses off patches and stuff and put a new commercial license on it, even when original developers did not agree to it!
worse, everyone else in OSS world ignored whats going on. google 'mame going commercial'. best threads were by Haze, but he has since hidden his posts and given up on the subject.