The point I was attempting to make was not whether or not it happens, but whether or not you agree with the tactic of photographing and investigating all who attend the protests.
When one ventures into public, all sorts of things can happen, that's my point.
We are in a war, and there are traitors in the United States.
If any of those protested and snapped, have a VERY suspicious background -- no I don't mean, marching in a zillion on anti-name-it parades, they will be looked at.
If they've got parking arrests. No. How about delinquent Taxes. No. How about transsexual operation? No.
How about if they have had multiple arrests for arson? Uh, yes. Known agents of the axis of evil? Yesss....
No, I would photograph trouble-makers and those leading the groups. I would also photograph those doing activities not in synch with the intent of the protest. I would also photograph those with large boxes and small attache's being exchanged.
Operative word of focus: "all". Do you really think two guys with a camera are going to photograph ALL who attend? This is fantastic lunacy.