Hi;
If I have to park my vehicle in a bad area , I try to have nothing of value laying around, I do not throw a blanket over anything - it makes people think of valuable items you want to hide to keep.
If the subject is going to be a gun rally, then the bad guys know that other people have guns and the BG's know to let you have your say, demonstrate as you will and then the BG's know you will leave their area and not take the chance of getting shot by many/any armed citizen(s). They (BG) will wait until the average sheep return to the hunting grounds of thier turf.
It would be nice to get the daily reports from the police as to when a pro gun rally is being held - just how much the crime rate in that area had dropped ?