If the APA manages to have students arrested for arranging a peaceful, legal protest on the internship issue, that is going to make them look far worse than anyone getting arrested. It would likely get us an army of pro bono ACLU lawyers trying to sue them out of existence, and a number of people with no connection to the field whatsoever rioting outside their headquarters. Come to think of it, that actually sounds like a pretty ideal outcome to a protest
I'm somewhat confused by the other things in your post. I'm hard pressed to think of one traditional university program where the psych department is off-site, and either way that does nothing to address the many other points that have been brought up.