Hee, thanks! I think maybe it is about the concept of home. When I fly in from Japan, the customs/Homeland Security guy will say "Welcome back" and smile because he knows where I live. The peeps who say "welcome back" are where I live. It's bedevilling to know that I could actually be deported for doing something innocent like driving my car with Washington state plates into the US while presenting my Canadian passport as ID. (I was told this by a friendly border officer yesterday, and I know him to be amiable because he didn't even ask about the stuff we brought in or how I got hold of a US child without his US parent in the car.)
I think Canadians have lower Security staff budget and officers need to move a lot of people through the line as quickly as possible. Getting through the Blaine port can mean a 3 hr wait without a special pass.
Seize jours trop tard, mon amie! Je suis retournée aux États-Unis.
I was okay with the border either way: I had full and proper documentation, and on the way back even segregated with receipts my Cdn purchases and did some mental math. Useless if the US thinks I've been away for nine months, which it did initially: my explanation led to a chat session about what to bring to the border and what not to bother with.