So, it sounds like there was a small number of such people. Of course, if that's not true, I'm happy to be convinced otherwise. I will not accept an argument based on guilt by association however (or in this case guilt by proximity which is even more absurd).
Finally, the truckers were protesting the federal trucker mandates (with their trucks no less) so it was not a particularly abstract demonstration. I guess these people were in the right location by your calculus but non-truckers should have disbursed to protest at their own provincial capitals. That is a reasonable argument but I think many of the protesters were also there in support of the truckers.