There was a piece in the San Jose Mercury News yesterday on left-handed shots in hockey. Some insight:
"Left-shot players far outnumber their right-shot counterparts. That disparity is especially seen among defensemen.
"You can't help but notice," said Jason Demers, a right-shot Sharks defenseman. "But I have no idea why. Nobody knows for sure, but it's weird." It gets even weirder. Canadian and European hockey players tend to be left shot while more Americans are right shot.
"I wish I had a good reason for why that is," said Mike Mountain, director of sticks and blades at Van Nuys-based Easton Sports. "But the reason there are more left-shot players in the NHL is because there are more from Canada and international markets than from the U.S.""
Except...It's not true. I don't know why it would be so hard to type "nhl who shoots left" into google and look my piece on exactly this topic - the fifth link down the page. You'd find that Europeans are much more likely to be left-handed shots than Canadians and Americans - who each shoot left in the same proportion:
In addition, defensemen are no more or less likely to shoot left-handed than centers:
I have noticed that among players who picked up the game in the US later in life, there are many more right-handed shots - most likely because right-handed people play right-handed in golf and baseball. But if you start playing hockey when you're a little hockey, it's most likely that your coach will put a left-handed stick in your hands and you'll learn to play that way.