You see, in Canada, the government offers significant tax breaks and direct subsidies to Canadian-made TV shows, in exchange enforcing a "Canadian actors only" policy for the majority of roles. But there are only so many actors in Canada, especially young actors. The country already has a relatively small population to begin with (about 35 million, roughly a ninth of the US population), and when you narrow the actors down to a specific age group (between 15 and 30, like most of the ones below), and then combine that with the fact that Canada has become a very popular shooting location for American producers on a tight budget, you're only left with a tiny handful of actors. Additionally, most of these actors often stay in Canada for the rest of their careers (though not always by choice). That said, some have managed to break out it; notably, Ellen Page and Aubrey Graham.
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