I do miss quieter shopping experiences and believe it or not, Muzak instrumentals. I also miss the sound the simpler electronic or older PC-based registers would make as the clerk keyed in your purchases; it printed the receipt line by line. Those were miniature dot matrix printers, usually built into the register. Some independent gas stations still use something like this, but I remember when department stores were still using DOS with the old computer registers and the shrill signature sound the receipt printer made.
I don't, however, miss the screaming/yelling/otherwise noisy kids or the obnoxious pop music most stores tend to play over their intercom (which this here millenial does not like).
I also don't miss the crowds or people blocking aisles. Has anyone ever encountered two people (or more) having a long conversation amongst themselves, in an aisle or in a major pathway? It always happens at the busiest times, too, like after everyone gets off work or on weekend afternoons. These people are usually oblivious to other shoppers and won't move out of the way. It's almost as if they might as well take a picnic table to the middle of the store, throw some burgers on the grill and have a big ol' family/friend/acquaintance/coworker reunion during peak shopping hours.
Oh, parking lots and shopping carts. If possible, I park far away from any shopping carts, usually off to the side of the store.