I know several people personally who say this exact phrase, yet they mocked the football players who took a knee during the national anthem at games protesting exactly this issue.
Obviously most sane people would prefer an effective and peaceful protest, but there has yet to be one for this particular issue. So I am hardly surprised it has become this violent, especially with members of the police force and the president antagonizing people further. Also, I would add that any protest of great size naturally has people who try to take advantage of it and turn to anarchy. Shutting down such rioters with force seems to exacerbate the issue, as police force is what is being protest—an understandably difficult predicament.