You make a false conclusion by saying that because individuals can't pony up large amounts of property tax, the city is not such an economic engine. The industries of the city make the money...Bay Street, financial services, medical e.t.c. Individuals support these industries, but their incomes vary widely. Some people are very wealthy, others aren't. A city contains a wide diversity of incomes. If you raise the property taxes precipitously, you'll wind up losing a lot of people downtown who've been there for decades, that perhaps don't make as much money. 

Additionally, go to statscan and you'll see that in 2011:
"By 2011, fewer than one in five (18.9%) people lived in a rural area"

It'll be even more now. So if most citizens live in cities like Toronto, it is the federal and provincial governments responsibility to pay for the infrastructure that services the majority of citizens. That includes Canada's biggest city, Toronto.