I haven't experienced almost any problem with smelly streets while walking or biking in Stockholm, Oslo, Copenhagen, Helsinki, Munich, Cologne, Amsterdam, Rotterdam, Barcelona, Lisbon, Prague, and the list goes on. The worst I can think of is some smelly alley or higher traffic road in Berlin, or when I was in Milan when garbage collectors were on strike.
The worst cities I've ever smelled were São Paulo, Los Angeles, NYC, and San Francisco. Guess what these cities have lots and lots of? Cars.
You want to be in a car to avoid smelling cars? That problem would go away if there weren't cars in the places people walk, see also the article and prioritising dignity rather than (say) breathing car exhaust.
But then again I suppose being pedestrian or cyclist in those areas would not help that one...