I'm not sure in Toronto, but in many countries in Europe, you can easily find markets at the outskirts, specially when talking about the industrial markets and big shopping malls (a mall is after all a market with diff shops, my city's malls are in a range of 2-6km from the city).
The market case is specially curious as, usually they were found in the crossroads of the nearby cities, and some even became proper cities themselves.
Same happens with the main stadium / arenas (my city's hockey arena is at 4 km from the city itself).
And industrial zones in my city can be found in a range of 2-15km from the city itself (and all inside the city/municipality area).
And you can easily find far away ports in ancient times (Ostia - Rome, Piraeus - Athens).
In Sweden for instance you find the university/campus towns of Lund or Uppsala dozens of kms from the cities (Lund from Malmö and Uppsala from Stockholm).
I remember in Barcelona that one of the biggest theatres, the Musical one, is quite far from the city centre (also the Grec one).
To me the district representation is pretty much spot on. Of course it doesn't apply to all possible cities of all possible cultures, but pretty much...