I've twice had my priority tagged bag left off a flight from YYZ to Fredericton while flying on paid business class tickets (even though there are no business class seats on that plane). My layovers in Toronto were over an hour in both instances.

I assume they left it off because the plane is too small to carry everyone's luggage? But why a priority tagged bag on an expensive fare ticket...on two separate occasions...

(I didn't expect one from the friendly staff in Fredericton as it wasn't their decision to leave my one bag behind)