Weird Digital Distribution Rules

My wife noticed something ironic on Netflix recently.  My wife likes horses and she saw a show that had horses with multiple seasons available for streaming: Heartland.  She started to watch it and she liked it.  As she watched the episodes, she realized the show is from Canada.  She remembered watching a video of Wil Wheaton talking about Netflix not being available in Canada.  This is because Netflix does not have the distribution rights to stream United States (I can't use the adjective "American" in this context) TV shows to Canada.  Why is it that Netflix has the distribution rights to stream a Canadian TV show to the United States?  Could it be that Canadian content producers want more people to watch their TV shows, not less?  If that is the case, then why would United States content producers want fewer people to watch their TV shows?