Rather unusual, especially when it comes to crossing the northern land border, and especially crossing that land border with more than one person in the vehicle.

It's fairly unusual for them to perform any search or inspection at the Canadian land border for Canadian or United States citizens or residents. I suspect that persons who are from nations which are considerably less diplomatically positive with the United States, and especially who have specific grounds for suspicion related to their identity or documents, would bear the brunt of searches in general and electronic device searches in particular.