Menay, Miny and Moe are running a country store, which means there are plenty of moving things: flies on the fruit, a sack of Mexican jumping beans -- when I was a kid, we had them, but they never budged -- and when they run out of lamb chops, one of them heads out to the pasture for a cute little lamb.
Most of the gags are about slovenliness and laziness; it opens with the three little monkey sleeping during the working day. I guess that was the image people had of country stores in those days, before the A&P came to town and made things mice, ad te National Biscuit Company meant you could buy crackers that some ne else hadn't already rejected.