Canadian here who has travelled to a number of Schengen countries and the only time I have been questioned extensively (albeit it is only one data point) is at Helsinki flying from Sydney, Australia to Frankfurt, Germany (connecting in Singapore and Helsinki). The officer asked me what I was doing in the country and explained I was there for a conference and then had to go into some detail about what exactly the conference was about, how long I planned to stay in the Germany and even had to produce my return itinerary. A bit unusual for someone who travels internationally fairly frequently.

-RooFlyer88