I see lots of non smokers say this, but I taught at an after-school music program for 13 years, walking through tight hallways with students and parents alike. I would even smoke on my 15 minute break. I was never once questioned or pulled aside or anything. I highly doubt that every parent of every student I ever taught didn't care. You're just smelling careless people. Plenty of people are around you high all the time and you have no idea.