Tobacco vending machines, as currently designed, need human supervision to set limits with underage purchasers. Right now, however, tobacco vending machines are dumb. They need our help. They need, at a very minimum, to be watched by responsible persons. This means they have to come out of the closet, literally, and the foyer, and the basement, and all the other places they have provided a convenience to smokers.
Most tobacco vending machines, although dumb, have the virtue of being simple.
They sell cigarettes, only. This makes them easy to supervise, when placed in plain sight of responsible persons. Minors have no business using them. Unfortunately, vending machines of newer design can dispense a wide variety of items, including snacks, candy, sundries, and tobacco. This makes them virtually impossible to supervise.