On Amtrak, a Word to the Wise is Usually Sufficient.

One of the things I appreciate most about traveling on Amtrak is the low tolerance of the on-board crews for problem passengers.  It might be a couple of inconsiderate college students who are talking loudly and annoying other passengers in the coach. Or maybe it’s a woman who tries to sneak a cigarette in one of the lavatories in her sleeping car. They will get one firm warning and, if there’s even the hint of a repeat infraction, they will be put off the train at the next stop day or night, big city or small town.
I was on the Southwest Chief headed for Chicago a few weeks back and the conductor made a terse announcement on the PA system: “Someone in this car just had a cigarette in one of the lavatories.  If it happens again, the very next stop will be yours!” And he meant it, too.
If the culprit ignores the warning and seems likely to cause a problem – a belligerent drunk, for example – the conductor will alert the engineer to radio ahead and ask the police to meet the train at the next station. The first inking the drunk has that he’s got a big problem is when he looks up to find two big state troopers beckoning to him.
If a troublemaker is really causing a problem, the conductor won’t even wait until the train reaches the next station.  He’ll have the train meet the police at a spot where the tracks cross a state highway.  I witnessed that on the old Desert Wind (since discontinued). We stopped in the middle of a Nevada desert and an inebriated fellow was escorted off the train by two husky state troopers. When last seen, he was in the back of a state police car headed for Caliente, Nevada, and a night in the local jail.
When someone is put off the train, they’re on their own. If it’s a long-distance train, the next train won’t be coming along for 24 hours and there’s no guarantee there will be space … and they’ll need to buy a new ticket. 
Let me emphasize that it doesn’t happen very often. One firm warning from a no-nonsense conductor is almost always enough to nip the problem in the bud. If it doesn’t well, good luck finding a room in Sandpoint, Idaho, at 2:30 in the morning!