This is a Jam Handy gem. Jam Handy did a lot of films for corporate generally illustrating sales techniques. Apparently they did this one for Dupont. Their premier customer was General Motors. Jam Handy was located a few blocks down from GM headquarters on E Grand Blvd. You can find a number of their films on Prelinger Archives. The last supermarket was a National Supermarket on Alcoy and E 7 Mile Rd. I recognize it. Lived about 8 blocks away. Notice in one store it is spelled "pasteries" Typical Detroit in the day - the planet was Saturin and Buttericks stuff was a "patterin" Sooo Detroit in the day. Useful film demonstrating sales techniques - like many of Jam Handy's films.