I cross the US/Canada border frequently while driving, and generally speaking the personnel there (in each direction) are quite businesslike. They appear to me to be quite serious about their work, but over many years I have had very few occasions where I might want to complain.

I am careful not to take photographic equipment with me that might imply I am working in the US - they are fairly diligent about preventing non-US residents from working without the required permits.

In the 1980s I worked as one of those Canadian border crossing persons, so I may have a somewhat different perspective on the issue.