By de-normalising smoking and making it cost prohibitive, kids are less likely to start and that's a very good thing to aim for. I don't care if adults decide to take up smoking - knock yourselves out - but kids get pulled and prodded by advertising far beyond what we'd expect. Why do you think Camel cigarettes sells cuddly Camel toys?
I was staggered when my then two year old daughter pointed out the McDonald's golden arches when we were out driving. She'd never had one, never seen anyone eat one as far as I'm aware, yet she knew what they were ("Donners! DONNERS!") and I put that down to advertising, pure and simple.
Think back a decade or two (ok, maybe further - I am old) and smoking and cigarettes were commonplace both in real life and on TV/movies. I'm often astonished by how much people smoke in movies I think of as quite recent (showed the kids Ghostbusters the other day... man, they puff their way through that film). By reducing the visibility of cigarettes we reduce the desirability. Ratchet up the price at the same time and the kids will soon balance up smoking with spending their money on cellphones or apps or something else. My kids already ask for their pocket money in iTunes money so they can buy One Direction (shudder) and that means they're less likely to try something like this out of their own pocket.
When smoking is down to about 5-10% of the population it ceases to be a societal problem and can drop off the radar. That's a huge win in my book.
Ironically, the only place my kids see people smoking for the most part is on anti-smoking ads... someone wants to have a think about that.