Im not sure this is either true or what you mean. Is it the conduct of the organization, which in fact promotes peaceful protest, civil disobedience etc as a way of highlighting racial injustice, that you find problematic or is it opportunists who coopt their protests to loot and destroy?
If the latter, which I suspect you really mean, then sure looting is of course bad. But instead of saying “I don’t dispute the ideology but we can’t have this looting”, we change our focus and say “all this looting must stop but we have to fix this problem that affects our Black fellow citizens”? These small changes in sentence construction belie where White America and White Britain view the priorities to be. The second recognizes the depth of the problem BLM is trying to highlight. The first pays lip service to it; I’m not a racist but....
To be clear I’m not saying you (MidA15) or anyone else is a racist for saying sentence 1. What I’m saying is that this kind of speech helps maintain the current structurally racist system that people of color are forced to navigate