Well, you know, I suspect a lot of people's attitudes to snails may be from inferior canned products. There are a lot of things like that that are seasonal, or at least best in season, and that cannot or are not produced but a few places. We can get only the poor canned or frozen version. Snails have to be gathered, confined, and held without food to purge them, and in the wild they are a seasonal thing and the subject or local festivals and such at which those attending speak highly of them. But they're no more the hallmark of French cooking than corn would be considered the hallmark of American cooking. (In most of Europe, maize, or what we call corn, is a food for animals. Italy is a notable exception.)
I guess a lot of what maybe the French would like French cooking to be thought of is demonstrated by the heights to which an accomplished cook can raise the simple steak and fries. Nothing fancy, but it requires meticulous technique. Nothing particular French about, except that the French are known for doing it wonderfully.