[struant]

There is no requirement to make money to have a successful open source project.

That being said. Monetizing open source is fine so long as people are up front about from the beginning. People are upset because switching the license is effectively changing the rules in the middle of the game.

It is like going out to a restaurant and in the middle of your meal they change policy from having free refills to charging per cup. Either policy is fine, but changing policies is a scumbag move. A lot of people would have never sat down to eat there if the extra drinks weren't going to be free. Especially if free drinks was the sole reason a lot of them were going there.