Some people say protestors becoming violent, vandalizing, and looting are isolated incidents by a few bad eggs, most of them are doing the right thing.
Really similar thought processes go into those two, usually by people you can sort into camps of opposing worldviews. They're both right and both wrong, but it's surprising how similar the lines of thought are and how people can't see the other side is thinking just the same way.
No one is condoning looting - in fact, it's just as frustrating for me in that it's distracting from the message. But let's not forget what the (much, much) bigger problem is. I also believe that various bad-faith actors (police, conservatives) are using the looting to distract from the fact that the police have systematically deprived us of our rights with no recourse.