Here's some information on Common Canadian fuel additives. It's a bit ambiguous...go figure.

http://www.ec.gc.ca/cleanair-airpur/CAOL/OGEB/fuels/reports/additives99/additives99_3_e.htm

I know that the big killer for stoves is Oxygenated fuels...commmonly added as an octane improvers...or branded as a 'winter gas' (maybe that's what 'Canadian gas' is?). They can attack the seals and such in your stove.

The more expensive the gas, the more additives...so I've always been told anyhow. If you use regular and not premium, I think the risks are minimal...though it might be a good idea to carry spare parts and a servicing kit anyhow.

Before propane was king around here my dad used an old school Coleman 2 burner stove and lantern for camping. He'd put gasoline in them even though you weren't supposed to and they ran fine. He claimed that as long as the quality of the gas was good, there would never be a problem. Also that the warnings originated from a time when crap gasoline was common, requiring 'stove fuel' be used.