I’m trying to come up with a way this might work and failing.
Hollywood studios are large public corporations. Or, more accurately, they are relatively tiny components of huge multinational public corporations. Public is the key. As just emphasized by the vote of no-confidence against Disney’s Michael Eisner, the performance of the studios is closely watched by their shareholders, which are mainly firms like state pension funds and investment corporations - business that have both enormous clout and a need for utter respectability.
So first it’s hard to see where the need comes to accept huge bundles of outside and illegitimate cash: the studios can either finance their own films or work with one another to lay off costs. And second, while everyone knows that movie profits are more fictitious than the story behind Hidalgo, the gross amounts and their distribution are very closely watched, so making millions in secret payoffs to the mob sounds more like a spec script than a sound business practice.
There once was good reason to make bad movies: Hollywood studios needed to amortize their sunk costs - the studio lots, the contract actors, the union workers, the warehouses of props, etc - by keeping them in use at all times. But this hasn’t been true for the most part in decades.
And it’s difficult to truly lose money on a film today, given Pay-per-view rights, cable rights, broadcast rights, foreign distribution, DVD and VCR sales and rental, soundtracks, ad placement, merchandise, and the million and one other ways studios have or recouping their investments in the long run. A major bomb can lose a hell of a lot of money in the short term, but studios have the luxury of long-term thinking, even if they have to fire the CEO to get there.
Now could be this true if we throw the studios out and go down to the level of small-time producers grinding out direct-to-video and late-night-cable programming? It certainly used to be true that the mob was in the movie business. Read Profoundly Disturbing: Shocking Movies That Changed History! by Joe Bob Briggs and you’ll get tales more lurid than any movie about how the mob took the hundreds of millions of dollars that independent unexpected blockbusters like Deep Throat and The Texas Chainsaw Massacre made.
But even those don’t quite match your scenario. The mob wasn’t exactly laundering money: porn and splatter movie-making was just another quasi-legitimate business they controlled. And they never put their money in to begin with: they just took whatever came in before the legitimate owners could find it. And this was decades ago, and even the world of the schlock producers has changed some since then.
So, maybe, sorta, kinda, possibly, in a certain sense, but mostly to my mind your theory doesn’t even come up to the level of a theory. It’s an accusation, but an unlikely one.