It's been rumoured that Dave Gibbons was paid somewhere closer to half a million dollars to, basically "bless" the Before Watchmen prequel series with a couple of sentences. But Alan Moore appears to believe he was offered a lot more. In an interview back in May at the Nottingham Contemporary, he told the Left Lion website;

Well, they asked me if they could give me a huge amount of money to bring out these Watchmen prequel comics – which they were going to do anyway – and that was probably a couple of million dollars. I should imagine with all of the films it would be another few million? In a way it's really empowering to do that.

You can't buy that kind of empowerment. To just know that as far as you are aware, you have not got a price; that there is not an amount of money large enough to make you compromise even a tiny bit of principle that, as it turned out, would make no practical difference anyway. I'd advise everyone to do it, otherwise you're going to end up mastered by money and that's not a thing you want ruling your life. Money's fine if it enables you to enjoy your life and to be useful to other people. But as something that is a means to an end, no, it's useless.