Notice that many of these services offer copyrighted contents online. I think the primary issues they had with doing business outside the U.S. is that there are less copyrighted laws to adequately protect the material and that sort of business in those countries. It would also be notoriously hard to sue people who abuse them.

Other services such as telecom have to deal with Canadian collusion and protectionism towards the readily established telcorps. It's an uphill battle. One that Canadians have been paying the price for, with high wireless phone bills, high internet fees and the recent attempt at imposing Usage-Based Billing.