[erdo]

That's interesting if true, because my gym in France (Neoness) just made me turn up in person to cancel my rolling monthly subscription, despite the fact that I signed up on line. (Obviously I will never, ever be giving them my money again regardless)

[Bayart]

As far as I'm aware the letter of the law is you can cancel with a formal letter (lettre recommandée avec accusé de réception), and that's the most bothersome it should ever get. They shouldn't have the right to ask that of you, and it's likely they're just taking advantage of people.