This is just a guess, but… I think the bacon was used as the source of oil for the frying, not for adding to the recipe. It was common 50–100 years ago to use bacon fat for frying, plus it added a hint of flavor from the grease. I guess the bacon was not added to the recipe. It may have been eaten separately, but the bacon was removed from the pan and the crepe cooked in the remaining hot grease.