The mob had interests in jukeboxes and entertainment unions and promotion companies, which not only allowed them to launder money and hide assets but gave them and their associates a cash cow to rip off performers, producers and songwriters through manipulation of sales, royalties, contracts and concerts/appearances. And if that failed there was the good old "Do what I say or I will hurt you" fallback.
The whole industry was and is dirty so it was sort of tailor made for them.
Hesh was probably based on people like Sidney Korshak or (especially) Morris Levy, who both turned Mafia connections into very profitable semi-legitimate business ventures.
Levy ran Roulette Records, which was notorious for Mafia influence. There's a few books out there now about Levy. I think Tommy James wrote one about his (dangerous and unprofitable) experiences with Levy and his crowd.
"When the snows fall and the white winds blow, the lone wolf dies but the pack survives."
Winter is Coming
Now this is the Law of the Jungle—as old and as true as the sky; And the wolf that shall keep it may prosper, but the wolf that shall break it must die.
As the creeper that girdles the tree-trunk, the Law runneth forward and back; For the strength of the Pack is the Wolf, and the strength of the Wolf is the Pack.
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