Dairy Isle was one of many soft-serve ice cream chains that popped up in the 1950s and 1960s. Most are gone now, with Dairy Queen being the major exception.
The first Dairy Isle was built in Wooster, Ohio in 1951. The chain expanded through Ohio then south to Florida and north to New York. I don't think they came to far west of Ohio. I don't recall any in Chicagoland. We had Dairy Queen and Tastee Freeze. The chain grew to at least 160 stores. It is now long gone.
The stores had the typical ice-cream shop walk up windows. Their distinguishing feature was an ice cream cone that cut through the roof. This website has a look at 40 repurposed Dairy Isle stores.
These are the backs of the discs. The only difference is that the 1976 discs have the logo in a purplish shade and the 1977s are red. The fronts and the checklists are the standard ones from both years.
Five Cubs in 1976...
... and two in 1977.