It won’t. They’re just banking on you forgetting you signed up so they can charge your card.

But If there isn’t any money on the card then they can’t charge you. Think of it as signing up with a gift card in a way. However the times that I’ve done it I haven’t been able to use a card with $0 on it. I’ve always had to put at least $1 on it so the card can be verified.

Idk if I explained that well

tl;dr: No