Problems ethanol causes in vintage cars?

Do they use ethanol in the gas in Canada ? I've never had a problem with my lawnmower or snowblower , they sit for 6 months and start right up . As for my cars , never had a problem , I use only 94 octane petro can gas on the 340 Dart , starts up no problem , never had any carb problems . I use de-icer in winter to help with any water in the gas freezing up and causing a no start , been using it for years without problem .
I think there is a problem with sub standard parts , not ethanol