Just to say I think your analogy here might not be appropriate. Smoking is banned for health reasons not for the smell (although personally I hate the smell too).
As for food smells, as long as people aren't disturbing my ears I don't have a problem with people bringing in other types of food. Personally the smell of fish makes me gag but doesn't mean I would begrudge someone else eating it next to me as long as they weren't throwing it in my face. I think as long as people are sensible and not disturbing others then its OK although I can understand why some food (pepperoni pizza comes to mind) might stink out somewhere. I think most people are sensible with food for the theatre and don't bring silly stuff in from my experience.
Personally I find the WDT a bit different to BT as its a live show and therefore you are also possibly disturbing the actors as well. I would be inclined to limit what I took in there to snack food but as others have said even these can be loud too and smell (doritos for instance). But banning any snacking just seems silly as it can be a useful distraction for bored kids etc.
Please know I wasn't saying that smoking in theaters has been banned just due to the smell. It was banned and deemed unacceptable long before the smoking bans came into effect in my location.
Just saying that the NICE smell of popcorn without the smell of tobacco is how I remember it years ago before the smelly foods were introduced.