I was at dozens in multiple cities. I did street theater, I participated GAs, I did direct action, I marched, I protested, I sang. I was on the wrong end of a baton, a boot to the solar plexus, a cloud of tear gas, and I've gotten a face full of pepper spray. I was quoted (anonymously) in news articles. I was on a committee, I had an affinity group.
There were many, many people. Sometimes 60k. No one told them what the right and wrong reasons were to be there. People were there because the systems in place did not serve or represent them. For some, that was because the police and prisons were tearing apart their families and communities, for others, it was because their 401k got wiped out.
As you should be able to infer, the people who lost their jobs and their homes are going to protest differently from the teenagers whose school got closed down. The people who just got out of college with massive debt are going to protest differently from the parents with kids.
No one was interested in telling people they were there for the wrong reasons, because nearly without exception, people weren't. People smashing windows had good reason to do so, and people doing building occupations had good reason to do so. The media, the police, and the people on the outside generally couldn't understand because it was different than what they know and understand. Politicians who made their career from coming to rallies couldn't understand people covering their faces because to them, protesting was about building a resume or street cred. The media wasn't used to dealing with people who didn't like them or who didn't want to talk to them. Outsiders couldn't understand why people just didn't want to vote some new 3rd party in.
That doesn't mean there wasn't a structure, that doesn't mean there wasn't a message, that doesn't mean it was incoherent. There were a number of threads pulling people together that weren't apparent in the first 15 minutes and might not have been apparent after a whole 2 protests. They were there and they're still there.
The police in SF vary, there are ~2,000. I've seen some people who seemed like nice people, at least at the moment. I've also seen some that took great glee in beating people. I've seen some that will look like one at one moment and the other the next moment. You've got to watch out for the 99% of cops that make the rest look bad.