Locking up isn't the only way to punish people. There's actually some talk about e.g. firing someone from his/her job for supporting a candidate. Recently, there was a long discussion chain in HN about how Y Combinator should sever any ties to Peter Thiel because he supported Trump. That Thiel "should be fired".
Discrimination at work may also be about free speech.
Right, and it's not because Trump is a republican. That's what people keep missing. Trump is a man who has openly incited violence against ethnic groups! Called for the deportation of muslims. He's called women fat pigs, and boasts about how he screws people in business. He boasts about avoiding taxes! This isn't GW, or McCaine...
Most organizations have a very understandable right to not want to be associated with that. It's called a PR disaster. Somehow Trump is immune, and I will never know how.