levi123, not everyone is quick to throw someone out.
My Rosh Yeshiva once said that when he was a bochur, there was someone in the yeshiva who had a gambling problem. He also drew others into his gambling in an attempt to pay off his debts. My R”Y went with a few other elter bochurim to R’ Shmuel Berenbaum zt”l and asked him to make this bochur leave the yeshiva. R’ Shmuel began yelling at them, “Who are you to say a bochur will be thrown out?! Do you know what can happen to someone when you make him leave a yeshiva? Such a decision can never be made lightly!”
R’ Shmuel ended up taking the bochur under his wing, and helped him through his problems. My R”Y didn’t say the person’s name, but told us he is a well-known talmud chochom today.
My mother has been working in the school system for over 25 years. She’s had times where she felt a girl needed to be kicked out, and never did it lightly. She always made sure the girl had another school to go to first. She always asked a shailah to a big Rav about it before she did it.