I've encountered hurdles like that, but most of the time, they aren't strictly due to billing issues, and more likely due to intentional restrictions coming from the seller. As soon as you have a credit card, pretty much all payment processors will happily accept to process your payment, wherever you are in the world.

I've had quite a few bad experiences trying to purchase internationally (if your billing address and your shipping address are in different countries, you're in for trouble), but I don't think BTC solves any of those. BTC doesn't solve the shipping part, and BTC doesn't solve the fact that some stuff isn't internationally available (for example, music/movies/TV shows).