We were once held up by a demonstration where teachers had taken over a toll booth. Traffic was backed up but was being let through after the teachers explained their grievance to each driver. We eventually got to the front and when they saw our Canadian plates they waved us through. Instead I stopped and offered them 200 pesos (less than the toll I would have paid) for their donation box. They were very pleased and practiced their English by giving us a brief explanation of their problems. I forget the specifics but it was the same Problem Canadian teachers had, class size or something.
As we drove on we noticed the Federali patrol cars were making u-turns before they came in sight of the toll booth, I guess what they could not see they did not have to report or become involved in. It was their way of showing support and letting the teachers have their say. I wish the police in Canada were near as understanding.