Whether some license was taken in depicting the male bond between Frankie Valli and Tommy DeVito in Jersey Boys (the musical and the Clint Eastwood-directed movie) about the life and times of The Four Seasons singing group may be beside the point. With any representation of a relationship, the viewer always has to think if he or she would have acted the same way for a friend. In both the show and the movie, Tommy is the free-spending gambler who ends up owing huge debts to the Mob, around "160 large." He also "borrows" from The Four Seasons account (the band sold over 100 million records during their career), to the tune of 500,000 dollars. In a scene that concludes with Tommy being banished from the group and to a life in Vegas where he can be watched by the people he owes, Frankie takes on the debt for him.
This is payback for Tommy having helped Frankie off the streets of New Jersey years before. Did Tommy lose/steal the money? According to an interview with repoter Vicki Hyman, Tommy said, "I'm not proud of what I did. I'm not ashamed of it either." So, for the purposes of discussion, let's assume Frankie did bail him out and consigned himself to years of performing in order to make good on Tommy's debt.