In this case, I disagree. A couple of opposing views:

- What if I was in an area first, say a park? Does the right to light up trump my right to be somewhere in that case?

- What if I have to be there? Does the right to light up mean that I miss my bus because I'm walking to another stop or do I just have to live with it if there is no other nearby stop?

Though I support legalization of marijuana, I agree with you: smoking of any substance should be prohibited where other people have to smell the smoke.

Well, it depends on what the rules are. If you are in a park (first, last, doesn't matter) and someone has the right and chooses to exercise that right to light up, you can either move, ask them to move, or deal with it. Same applies to the bus stop.

Let's use an analogy:

What if someone was burning a tyre in my neighbour's garden directly affecting my health?

You can't up the ante and claim it's analogous. Burning a tyre releases a tremendous amount of thick black smoke, burning a joint releases several orders of magnitude less smoke, and unless you're within 10m of the person you realistically are not going to be affected.

For effect: "What if someone built a rocket launch pad next to my house and it was directly affecting my health?"

Doesn't that depend on how far my neighbour is away? Perhaps we have 500m long gardens...

The analogy is valid as is "pissing over my fence onto my head", "kicking a football through my greenhouse", "catapulting dog shit into my garden" etc etc.

A smell that you don't like isn't comparable to destruction of your property or having toxic waste thrown on you.

I have a neighbour that often cooks curry; I can't stand the smell of curry. Even though the smell comes in through my windows, I don't have the right to force them to stop cooking. I just close my windows.