It's not the money per se, but the money produces the cache. The Tournament has grown on me, in part because of how serious the player are taking it. It's kind of like back when the All Star Game was taken seriously. It is now a complete joke.
I saw a good tweet about how this is a TEAM accomplishment as well where they can go win something together. Outside of winning a title, there really aren't a whole lot of team goals where you win a trophy/ring and can call yourself the best. Almost everything else is in individual accomplishment.
And all these dudes are just hyper-competitive. They wouldn't be in the NBA without that drive of just wanting to win and be the best; they added something new to go win so they want to be the best at it and go win.