As far as I can tell, the ingredients aren’t significantly different between the US and Canada -
USA:
Chicken McNuggets® (10 piece):
White boneless chicken, water, food starch-modified, salt, seasoning [autolyzed yeast extract, salt, wheat starch, natural flavoring (botanical source), safflower oil, dextrose, citric acid], sodium phosphates, natural flavor (botanical source). Battered and breaded with: water, enriched flour (bleached wheat flour, niacin, reduced iron, thiamin mononitrate, riboflavin, folic acid), yellow corn flour, bleached wheat flour, food starch-modified, salt, leavening (baking soda, sodium acid pyrophosphate, sodium aluminum phosphate, monocalcium phosphate, calcium lactate), spices, wheat starch, dextrose, corn starch.
CANADA:
Ingredients:
Chicken meat, water, modified corn starch, salt, chicken broth powder (chicken broth, salt and natural chicken flavouring), seasoning [(vegetable oil (soybean and/or canola), extracts of rosemary, mono,di and triglycerides (from sunflower oil) and soy lecithin)]. Breaded with: water, wheat flour, yellow corn flour, modified corn starch, salt, baking powder, spices (white and black pepper, celery seed), wheat starch, whey powder, sodium aluminum phosphate, corn starch, partially hydrogenated soybean oil (manufacturing aid) and cooked in 100% vegetable shortening [Partially hydrogenated vegetable oil (corn and/or soybean and/or canola oil), cottonseed oil, partially hydrogenated cottonseed oil, monogylceride citrate and propyl gallate added to protect flavour, propylene glycol.]
It must be the packaging, then - we use really expensive cardboard here.