It comes up every time we have a giveaway on our site: "Why can't you have a contest that includes your readers in [insert not-U.S. country here]? This is the 21st century. What gives???" We know. We hear you. It sucks.
Here's the skinny: while we would love to offer a contest open to ALL our global readers, it really comes down a legal issue. Each country (and even some provinces within countries- Canada, I'm looking at you) has their own rules regarding sweepstakes and contests. What might fly in one place is considered illegal gambling in another. Maybe someday laws will catch up with our inter-connected world community. Until then, we are just going to keep trying to providing what we can to the most people possible.
And if there are any crack legal scholars out there who have found a loophole, let us know! We'd love to be able to give prizes to everyone!