The difference between Canada and the States...

On Monday Stephen (Steven? Stephawn?) Harper was on Corner Gas. He is the second Prime Minister to appear on that show (Paul Martin was on it in the second season, in a hilarious opening sequence). The Prime Minister, the leader of our country on a sitcom. I realize this isnt the first time major Canadian political figures have done this, but most of the other forums I have seen this happen in were political satire like Air Farce or 22 Minutes. But Corner Gas. It's not like you ever see... tonight, on a very special Everybody loves Raymond... George W. Bush! or... tonight on Friends... Phoebe falls in love with a saxophone player, guest starring Bill Clinton. Why does it seem absurd in an American context and not in Canada?