It also depends on the case officer; in a good/bad mood, not aware of free movement of EU citizens e.g. in my wife's case. So I would suggest you to be prepared for the worst. Bring along your tickets, boarding passes, health records etc.This is strange and worrying. I'm an Irish citizen by birth and I visit Ireland at least once per year along with other EU countries. Our passports are never stamped due to free movement of EU citizens. I say it's strange because I know many EU citizens who have gotten their Canadian citizenship with no issues. It's not like IRCC are not aware of how passports work in the EU.