GQ has a long, outstanding interview with the cast and crew of Goodfellas, celebrating the twenty year anniversary of the movie's release. Among many, many great bits, there's this revelation that many of the extras and bit parts were, um, typecast:
[Writer Nicholas] Pileggi: We'd put the word out [to the Mob guys]: "Anybody who wants to be in the movie, come." [Director Martin Scorsese] must have hired like half a dozen guys, maybe more, out of the joint.It's ten pages long, but if you've ever seen the movie, I dare you not to read the whole thing.
[Ray] Liotta: During dessert, it was like they started auditioning. "I knew a guy who beat somebody up." "I knew a guy who stole this, who stole that." They seemed to be talking about themselves, and they kept topping each other.
Ellen Lewis (casting director): We were told I could consider some of them for the film, but others were a little too hot to be considered: "That guy can't be in front of a camera." It was actually the least likely-looking guys.
Pileggi: Warner Bros. now had to put them on the payroll, and they wanted their Social Security numbers. The wiseguys said, "1,2,6, uh, 6,7,8, uh, 4,3,2,1,7,8—" "No, that's more numbers than you need!" They just kept reciting numbers until they were over. Nobody ever figured out where that money went or who cashed the checks.