IMO, they can smoke in public all they want, with the following regulations:

1) If you burn me with your cig through negligence on your part, I get one free kick to your groin.

2) Punishment for litter of butts (unlit) : you have to eat them.

3) Punishment for litter of butts (lit) : same as rule 1.

4) Blow smoke in my face : I get to hit you over the head with the Manhattan phone directory.