The entertainment industry has a long history of making successful movies appear unprofitable on paper to avoid paying royalties.
Oh, and it's even an example in that Wiki article you linked lol
Dave: But movies cost millions of dollars to make.
Robert K. Bowfinger: That's after gross net deduction profit percentage deferment ten percent of the nut. Cash, every movie cost $2,184.
The contracts that celebrities get on adjusted gross (adjusted is doing 100x the work of the word gross in this context) have no specific entity revenue in mind. If costs show up later after some cash has been distributed, people absolutely freak out to give money back, so you need an arrangement that works such that that doesn’t happen.
Plenty of agents over the years sold celebrities the idea of gross on first dollar and couldn’t be bothered to read the proposed contract which led to many publicized lawsuits.