Some form of backup heat is considered rather essential in many parts of Canada, including in suburban detached homes. A small fireplace-style natural gas burner that doesn't need electricity is common -- I think about 1 in 4 homes have one? A significant proportion further have something else, like a wood stove, or bottled gas.
When the grid goes down for an extended period, people can and do freeze, or suffer the effects of poisoning or fire, from less safe forms of heat used out of desperation. (BBQ grill or wood/trash fire indoors, etc.) The Quebec/New England region grid collapse during the 1998 ice storm was particularly bad with dozens dead. An atypical event, but many do plan for that kind of eventuality in some way, whether by having backup heat or hopefully knowing someone who does.
When the grid goes down for an extended period, people can and do freeze, or suffer the effects of poisoning or fire, from less safe forms of heat used out of desperation. (BBQ grill or wood/trash fire indoors, etc.) The Quebec/New England region grid collapse during the 1998 ice storm was particularly bad with dozens dead. An atypical event, but many do plan for that kind of eventuality in some way, whether by having backup heat or hopefully knowing someone who does.