If we get frustrated with these peace activists, we must think that they can think another way, i.e. that we could argue with them and eventually prove them wrong. (Otherwise we wouldn't get frustrated and would just ignore them, like I don't care what my cat thinks about the military.)
That said, we must try to empathise (as best we can, though I do not believe 100% empathy is at all possible) with them and attempt to find the best parts of their argument. Sure its superficially clever to poke fun at those peace activists who are too busy smoking weed to come to 'their own' protests, but, this attack on the weakest proponents of peace is simply knocking down a straw-man. In the words of Antonio Gramsci, it is akin to 'a man who cannot sleep because of the moonlight and who exerts himself to kill as many fireflies as he can, convinced that the light will wane or dissapear.'
Surely we can agree that, even if there is no good argument for peace activism, there is a large and vocal part of Canadians who have some affinity to it. To shut them out as irrational (without much reflexion) is to wall oneself off from free speech and perhaps further the military/civilian divide.
To say the protests that turn violent are caused by hatred is to use exactly the same theory that peace activists use against the military. They see combat: they see disorder, they see murder. To any military person, there is order in battle and while it might cause hatred (in specific instances), to say the reverse is confusing effects for causes. I doubt many generals write their orders on the wrong end of a range, just as I doubt many of the protest planners hold meetings in gas chambers.
Also, some of the persons protesting are the Communist party, which is distinctly anti-militarist and has been for its entire existence. If anyone's position is well-thought-out, theirs is.
PS. I know Gramsci, whom I quoted, was a communist but the straw-man fallacy is a common notion in argumentation & his wording was the most elegant knock against it.