In the "Hardware Store" scene, Ed (Harvey Korman) refers to his store as "Central Hardware". There are several more lines that place the scene in "Central Hardware". Momma makes a comment or two about how she'd rather go to shop at Acme Hardware as it's a better place to shop.
Look carefully at the reverse image of the store name in the front window. It says ACME HARDWARE. Wrong name on the window, or wrong name in the script.