Instead of the garbage men joining the strike, why not load up all the garbage in the areas where the working class folks live and dump it all on the doorsteps of the politicians and business owners advocating for the increase in retirement age? They could also bring it to any government building and completely block entrances and exits. This would grind things to a halt even better.
I think this would send quite the message while not making the people fighting for their rights have to live in filth.
Edit: I don’t know anyone over there but if someone does, feel free to pass the idea along.