Google is right.  They may or may not do it.  Aside from Canada, when you fly home, you have that same situation again with US customs.  Sometimes they don't stamp, sometimes they do stamp.  I have seen them do it both ways with my US passport, whenever I return home from another country.   I am talking only about going through customs at an airport.  Both the US and Canada never stamped anything in my passport, ever, when I have driven back and forth, and I have done that dozens of times.

flying in and out of Canada on a weekly basis and my passport was stamped every time ...

Are you concerned about a visible-to-the-eye stamp that you don't want a friend or relative to see? Or are you talking about a government record of your travel from Canada?  

If it's not too late, you might consider adding the Card version of your regular P-Port. There isn't even a place to stamp it as far as I can tell. Of course, there might be an "electronic stamp" encoded somewhere, but not a visible stamp for someone to see.  

The Card is only for travel from some countries and Canada is one of them.  

I have flown to Europe and not had my passport stamped... and other times it was.  I doubt if you can know for certain.