Weed smokers are like crossfitters, or vegans, or people who run ultramarathons, and Canadians. They will die on the hill of convincing you that, not only is it harmless, you should probably be doing it too.
Most of the rest of us just kind of go, "Eh, it's not for me and I'm not convinced it's harmless."
But they will not allow that ambiguity. They must convince us to agree with them. Smoking cannot simply be passively allowed or ignored, and it certainly can't be questioned, it must be celebrated!
As with the other types of people mentioned, it is exhausting.
*Said with only a hint of sarcasm. Only a hint.