Canadians: how do you know how to pronounce your fellow countrymen's names?

I’ve wondered this a number of times while watching the Olympics: how do you know which names to anglicize and which to treat with the French pronunciation? (I’m sure the announcers are given a guide. I’m asking about you, the ordinary citizen.)

To be sure, the U.S. and most other developed nations are highly multicultural now, and we all face challenges to pronunciation. But it seems to me that an officially bilingual nation is a special case.

Do you have to learn each person’s name preference individually, or is there some other clue?

When you see Joannie Rochette, how do you know to say zho-ahn-NEE and not JO-nee? When you see Scott Moir, how to you know to say MOY-er and not mwah’r?

Do you know people who spell their names alike but say them differently, one with French pronunciation and one with English? How do you avoid irritating people all the time by making wrong guesses about their names?