Really straining the limits of this sublemmy with this one

I think it’s a question of language. If you’re a publisher printing an English language book in Canada, you can expect to sell it to English readers in the US and Canada, so it is efficient to print the price for both on the same printing run. You would probably expect not to be selling books in English in countries where the primary language is not English. In other words, probably for the same reason that English language books don’t have the price for Spain or China.

Boost

Another vote for deep Rock galactic.