Thats a good point you've made there. I know some people that cannot drink because it gives them migraines. Same way not everyone can eat chocolate due to lactose intolerance. While cannabis can be good for a lot of people it can also be bad for a lot of people. if it was legalised im almost sure it would never effect those people as they wouldnt have to come into direct contact with it. My mate has really bad asthma but sometimes when i do a hotbox, he just sits in the room and gets a little stoned because he enjoys the chilled feeling. he cannot smoke due to his asthma as it could induce an attack but even still he enjoys the occassional high.