20k out of whose pockets? Cube's? The director's?
Faizon agreed to 2500. The man had a few lines in the movie so why is he getting $20k?
Felicia getting $20k too for a bit part?
They didn't write, produce, edit or do any behind the scenes work so they don't get paid more. They don't get back end money because it's not in their contracts.
Actors take roles in low budget movies to hopefully raise their profile and get more roles. They want a bigger payday tell their agent to find their next project.
This is how the business works. Stop acting like people gotta hook somebody up outside of what's negotiated.