Because the police also protects them. Any old fashion violent revolt will be not greeted by population (currently) and the police and government will prevent that with force. the funny thing is, that the police and co. consistently protect the interests of the rich more than the interests of the poor. you’ll barely get discriminated if you’re rich. and it happens often, that rich people in a city are known by the policemen and they know that they shouldn’t fine them - as otherwise they’re out of their job.

Many people actually have forgotten, that unions were created because the workers were starting to kill owners of factories/companies due to the massive exploitation. Unions were only powerful, because the alternative - namely violentl death for the owners by being outnumbered - was actually dangerous and had teeth. but these days, unions have much less teeth - and when strikes don’t work, violence becomes necessary.