IIRC, Some sects of Sikhs do not insist (or perhaps even shun) the wearing of the turban. I think the original core population of Sikhs that emigrated to Canada were mostly these non-Khalsa Sikhs.
I'd say this is not entirely correct. There is no sect of Sikhism that shuns the turban to the best of my knowledge. And, I think there is this gross misunderstanding that you have to wear the turban to be a Sikh. As a Khalsa, you have to have unshorn hair, and turban is a practical way to cover it up. In fact, turban isn't mandatory when looking at the technicalities (there are a lot of Sikhs who might disagree with me on this). The Kes (unshorn hair) are. And, that too is a requirement only for Khalsa. I'm a Sikh (not Khalsa), but I keep unshorn hair and wear a turban because I like it. And, there are a lot of people like myself. A lot of non-Khalsa Sikhs wear turbans as a step towards the path to becoming a Khalsa.
