It's still better than living in Dunkerque (city) or « la Creuse » (region). Jokes aside, there is plenty climate that weren't too different from Quebec region in metropolitan France. And new territories leads to new opportunities, for lots of people. France wasn't always that rich and for some people, starting a new life in that region could means a new chance in life.

Same thing for every migration movement at that time.

Source : I'm French, and I live in a region that look a lot like St Laurence Gulf's region in term of climate.