The bread I buy is quite solid, i.e. organic stoneground wholemeal so could go in first!I unload the same way at checkout. Bread, chips and produce last so no crushed bread or bruised produce.
I wonder if others do what I do - I always put the meat/poultry/fish in a smaller plastic bag that has the milk carton in it and tie them up together. That way it stays fairly chilled until I get home, since I walk and take buses.