Anyway, I'm not so sure that's relevant. If Amazon or Microsoft pay less for the same role and skill level in their Vancouver office than their Seattle office, why wouldn't a Canadian company do the same? I don't think the pay differential is due to patriotism by upper management, so I'm not sure it has to do with where the company was founded.

In some cases proximity to the head office may be seen as worth extra pay, but that isn't always the case either.

The reasoning seems to be "we pay less in Canada because we can", and Canadian companies like Shopify or (in the past) RIM play the same way.