I dunno if its because they check your ip address. I always use one account on the home wifi and the other on my mobile signal. I had trouble using the same payment method previously too, so now I just use a different card for each, or one on card then one on paypal.
One for US, one for Canada
Can't be at the same address though. I tried setting up an account for the other half, and the order was repeatedly rejected. Support told me it's one per household, not per account. Note: this was for a previous promotion, but presumably same logic.
I got 2. Create another account with different email.
Haha! Yeah, we're keeping a low profile in here and hoping the feds don't find us. I hear they're cracking down hard on international game-buyers...