Reminds me of a story about Mario Puzzo:

When he signed the contract for The Godfather to be made into a movie the royalties he'd receive were to come from the net income of the movie, not the gross. Due to the accounting practices described in the article the film hardly made any money on paper (it grossed a lot but had exaggerated expenses). Already wealthy, Puzzo bet his royalties (a fraction of what he expected) on a roulette spin and walked away. The moral is to always get a percentage of the gross, not the net.