Satellite radio is not allowed into Canada because it has the potential to put Canadian commercial radio stations out of business. Canadian commercial radio stations derive their revenue from advertising sales and if their audiences decline because of satellite radio then they risk going out of business as advertising revenues fall.
The Canadian Radio-television and Telecommunications Commission (CRTC) under the guise of Canadian cultural protection has outlawed satellite radio to protect the interests of commercial radio operators.
Canadian radio business are using Canadians' penchant for collectivism to protect their own interests at the expense of the individual consumer. Sound familar? Free speech be damned - save the existing radio stations! People might not listen if they have more options!
I hope a black market develops to render these laws obsolete (working essentially in the same way the internet does to undermine collectivistic theivery).