In a number of the grocery aisles and especially in the laundry detergent aisle with all the vivid colors, after the first 40 seconds it often blends in to one kaleidoscopic mass.
Closest grocery store to me is a Super Walmart which as well as groceries has dry goods, clothing, hardware, and such.
The place is huge. Groceries are all on one end of the building, that helps.
For a time they had video ad players on some ends of the grocery shelving - too much, sensory overload.
They may be gone now, don't recall encountering them the other day.
Televisions are in middle of back wall of building and I try to get past them quickly if I have to go that way: too much flashing, too much noise.
Fortunately the place is open 24 hours and I can go at 2am!
Sometimes there are more people there than one would expect in the middle of the night.
I'm ok with supermarkets and I like spending time in empty aisles like stationery supply, pet products, baby toys or kitchen equipment. I pass the crowded parts like groceries super quickly and end up with a lot of half useful things and without something to cook
It helps to live in a less populated city but if I need to spend long time it does overwhelm me and I become totally spaced out or dissociated. I only rarely can't hold it together anymore and start to cry which is kinda humiliating though less than a full meltdown.
Actually I never really go to supermarkets unless I really wanna spend time looking at toys. But I can always go to the grocery store (a tiny tesco) almost next to my house and buy food quickly.