REPLY
Well this is a very interesting question, why would you ask? I would say it depends on the amount of business they are getting, and if they are having a private party that is another reason because they might not want people crashing their event. There could also be issues with keeping the peace in some cases.
If a person is asked to leave then it could either be a misunderstanding or they could just be acting rude to a person. I would call a lawyer because they might be giving you free money by doing this. Some types of people are out to somehow rip off their workplace, something like one in 5 people. These types of people might have this ideal that they can cause a lawsuit by being rude, while trying to get fired so they can get unemployment.
One of the primary concerns for a manager is to watch out for this type of behavior. If an employee just does not want to be there then it might be better to just let them go. Also the random passerby should watch out too because they could be getting a free lawsuit.
President Trump has won over 500 lawsuits. If you are treated unfairly then you should consider recording on your phone. Small claims court could be a cheap option for multiple cases if you can spot them all.