He said he broke up with his last girlfriend because she was beginning to 'crowd' him. [=she was not allowing him enough privacy and independence]
Her parents are concerned that she's been hanging out with 'a bad crowd'. [=with people who do illegal or immoral things]
He was never one to 'follow the crowd', so we weren't surprised when he dropped out of college to start his own business.
(..) Sure, it'll change your whole life for the better, but that's all. What the hell do you think you're doing? You got the crowd together, so I thought I'd do a little selling. I'm trying to raise a posse here. A short presentation. (..)1969 Butch Cassidy and the Sundance Kid