The worry of violence is mainly a risk assessment thing. No, I don't actually think there's much chance of getting hurt or arrested or whatever... but as I said, I really really reeeeeally want to go to MFF and I don't want *anything* to spoil it. Plus, it's cold out today. I don't want to catch a cold just before leaving town.
I fully support the message of the protest. I can think of no good reason to forbid two people who love each other from getting married just because they're both guys, or both gals. But the timing for this demonstration is just bad for me right now. So, I wish good luck to everybody participating in demonstrations in their own cities.