Well, at this point in my life, I look like the last person to light up a doob. (God, I can't believe I just said "doob". That's a first.)
I've never smoked pot and never will. When I was in high school, I took a certain amount of pride in being the only human being on campus who did not smoke pot. Actually, I don't think Mr. King, my history teacher, did either. Everyone else did, though.
And yet, people often assumed I was on drugs. I'm not sure what other people saw, but I spent most of my high school days with a pretty thick barrier between myself and other kids. I live in the same small city where I went to high school, and once in a while someone will come up to me and say they remember me. I never remember them. They list off a whole bunch of names of people they hope I'll remember, but I never do. I do remember that the teachers smoked dope, though.
Also, when I was in the Air Force, I requested to be transferred out of a job that involved flying, because I couldn't cope with puking my guts up every time we flew. I had to take a drug test, because it was assumed that only a drug-user would be crazy enough to not want a flying job.