In retrospect, I tended to play SimCity 4 this way; your simulated cities don't start to densify until you reach a necessary critical mass of population, and in order to reach that mass it's pretty much necessary to zone light residential over huge parcels of wilderness until enough people move in - and even then, it's tempting to just continue doing that until your city physically cannot expand anymore, since it's an easy way of bringing in tax revenue. In this respect, simulated cities have much in common with real ones.
This way of doing things particularly pronounced in the Greenbelt, a large area of protected land set aside by the Government of Ontario that's supposed to be off-limits to development, as it includes among other things the fragile and vital Oak Ridges Moraine. Despite this, it's being nibbled away in a dozen places, as are other undeveloped rural lands in the GTA - witness the example of the Regional Municipality of Durham, where recently Ajax was the only city to argue in favor of densifying the existing built-up areas rather than just laying down new suburbs - and it may only get worse, with the Toronto Star's recent coverage at how the Greenbelt may have truly been successful at pricing the housing market beyond the reach of most people, which - combined with the general lack of family orientation in Toronto's recent condo boom - has created an intense pent-up demand that's ready to erupt, bulldozing every farmer's field in its way.
The ones that have managed to hold out this long, that is.
Suburban sprawl in the Greater Toronto Area - probably some part of Mississauga, considering the descent path into Pearson.
Demand should not be the final arbiter. To be blunt, the continued existence of the Greenbelt, as a protected buffer zone of wilderness and country lands of the sort that used to be dominant in southern Ontario only decades ago, is more important than the popular desire to have a house with a white picket fence. No one is entitled to home ownership, not the same way we're entitled to things like free expression, and we'll be dealing with the consequences of that meme dominating our society for decades down the road. Still, the real problem here is that the government seems to have fumbled the ball so horribly that there are almost no alternatives to a house if 1) you want to own, not rent and 2) you are a family. With the forest of condominums in downtown Toronto thickening every day, and more and more new stands appearing elsewhere in the GTA, there's no excuse for this kind of residential myopia. Thanks to years and decades of poor decisions, Ontario may be on the edge of a housing crisis.
This would be something very instructive for the Lower Mainland to learn from, because damn if it's not a lesson that doesn't need to be applied to Vancouver itself. One of the reasons I live in New Westminster is because even rental prices in Vancouver itself were pretty much uniformly out of what I considered to be my league; as for owning a home in Vancouver, unless you want to be in hock to the bank for fifty years, forget it!
Yet Metro Vancouver particularly still has the advantage of time on its side - the pressures haven't been as great, it seems, and they didn't start as far back as they did around Toronto. There are still spots of open countryside that are reachable in under an hour by bicycle from New Westminster. The Lower Mainland doesn't have any equivalent to the Greenbelt as far as I know - if it does, please correct me - and if that's to continue being the case, I'd very much like it to be because the right decisions were made and the demand for leapfrogging subdivisions into the countryside just doesn't exist.
Besides, even if there is, it's not necessarily a good idea. I wouldn't want to buy a house on Lulu Island, considering what's going to happen to that land when the Big One comes.