"Oh boy, it's a boys-only party ! There'll be Jim, who never sleeps, and Jimmy, who's capable of anything. Charlie and Mike'll be there for sure, they're always so excited. And Nick... man, Nick just has that thing, you know, he's so fascinating! Sure, Andy can be a little cold (and let's not mention Bill...), Al is a little too loud sometimes -especially when he drinks too much with Big Boy Izzy-, but man, even Henry will be there, and we don't see him around much anymore ! Oh George, won't you come ?"
But George won't. Why ?
Hints :
As visualnotsobasic suggests in the comments. All names here refer to historical figures. All are men, including George. All these men had the same occupation. The names given are nicknames of their actual names.