Not a problem because a) tobacco is still legal (for now) b) two are not addictive and c) if one partakes of all three, they can still function perfectly normal, lead perfectly normal lives, and hold down jobs, raise a family etc d) you can't OD on any.....with weed/hash, if you smoke too much you just get too lazy to roll another spliff or pack a bowl......if fact, if you do weed/hash you become LESS dangerous to society, not more lol.....
You could compare this addiction to alcohol too but the big difference there is SOME people get addicted to alcohol whereby ALL people get addicted to crack, meth, heroin. It is not a casual drug. You try it, you get hooked, EOS. Now some maintain a reasonable life while partaking, but the vast majority head into a downward spiral onto the street, crime, etc....