I really hate shops, malls and supermarkets. I'm not easily overwhelmed and can handle being there fine. But it's just horrible there. Way too loud, bright and often too warm. Completely full of chaos and way too many useless products.
When I have to go I try to be out there as quickly as possible. I always thought that's weird, shouldn't those shops be designed in a way that makes me want to explore them, look at all the things they have, instead of just hunting down exactly what I need and leave as quickly as possible.
Whenever I go shopping for a single, most trivial item, I really need to psyche myself up. Those critical moments just upon entering the store are the key.
Because immediately upon walking in the door, you are immersed in a "shopping environment". Everything you smell, hear, see, touch is geared to making you spend more and purchase more and grab more useless stuff off the shelves.
Even in a Goodwill or similar thrift store you are subjected to these merchandising tricks.
I have found that keeping a very good household inventory on a spreadsheet is critical. If I have this spreadsheet on my phone and I refer to it, before venturing into aisles, then I know exactly what I need to purchase, and where to go to find it. Sticking to the shopping list, I can avoid the needless purchase temptations.
At Costco when I'd go with my parents, it was the custom of the cashiers to ask, "did you find everything alright?" and my father would always joke, that if enough people answered in the affirmative, that was their cue to rearrange the store and shuffle everything around, so that shoppers would get lost, and not being able to find what they want, would discover more useless stuff that they would pull off the shelves on impulse.
It also doesn't hurt to follow the advice of "never shop while hungry"!
They make it hard to find what you want on purpose in hopes you will be distracted and buy other crap along the way. I think it must work on most consumers.
I have the same reaction to it as you.