Coffee breath? Cinnamon gum? MAYBE you'll notice those things a foot away from someone in a one to one conversation. I can tell someone is smoking a joint across the street. I can tell the person in the unit below me is smoking weed. I can't tell you if they had coffee, cinnamon gum or are wearing perfume. The strength isn't remotely comparable. Car exhaust, while not great doesn't have even close to the bad smell weed smoke has.

And I live in country with already legal and easily accessible weed with a wide variety of strains. I don't think I'm just smelling skunk weed.