None of the guys I knew who can do it ever lived in cities.
I've lived in smaller cities, even a city with a pulp mill...
I can really pick up the smell that they put in natural gas too... even if others can't smell it...
???
I now live in a city ,and I smoke,and can still do it,sometimes you can pick up the scent on approach before you see them when they are in full rut.....a combination of the musk of the tarsel glands and the fact that they urinate on themselves,big ole ruttin bucks reek!