Thanks for you reply.
I'm not trying to evade taxes or get into legal trouble. It just looks like it is easier to start (and maintain) a US company and get a Stripe.com account, than it is to get a merchant account and a payment gateway over here.
Because the US company is simply reselling the subscriptions, every sale will be passed through to my company here, so I don't really see any tax headaches.
I am simply wondering if it is legal to use a US company for this.