Parallel to that, I have to imagine Costco makes a lot of money off of impulse purchases, which are induced by uncertainty in the specific items they will have available, plus mutable store layouts.

Long ago in undergrad I took a retail marketing class and we did a field trip to Costco; the GM told us it was part of their policy to rearrange parts of the store occasionally so that you had to browse the entire place to check off your shopping list. This increases the likelihood that you stumble across new products. So it’s this combination of “best price/quality without decision fatigue” plus some impulse buying that works for them. The fact that they are figuring out the price/quality trade off for you up front probably also makes it easier to impulse buy with fewer regrets.

Yeah, this right here. I don't want to sift through thousands of options. Sometimes I just want a widget that is good quality and I don't want to get ripped off.

It's a gimmick only for those who get sucked into buying things that they don't need. I've been a Costco shopper for decades, and sure have succumbed to some useless stuff, but my Costco list is 90% the same month to month. I get appalled when I see the same items on my list, that are smaller and in a pack of 1 instead of 2-4, for more money at other stores. If electronics were just like food, it would be like seeing a Macbook Pro for $2000 everywhere but it was $799 at Costco.

Some companies serve the people and some companies want people to serve them.

The sabbath was always meant for man and that makes a lot of people very angry because whatever ideological or religious lip service someone gives their behavior demonstrate they hate man, or more subtly, love mankind like dollars in their pocket, stripping humans of their humanity.

This mendacious attitude is also a major driver of enshitification.

The internet and executive social distancing has made a huge swath of people lose touch with how unique individuals are, so they treat humanity with the bigotry and coldness that the law of large numbers has lead them to, which is ultimately very mean.

A specialty shop can probably survive Costco much more easily than they can survive Walmart or any other conventional (American) grocery store. The grocery store carries 20 or 30 different olive oils, to select one example. Odds are all the snobbiest will find something they like... odds are even decent that in a blind taste test even the snobbiest would find something that they would be horrified to discover came from a normal grocery store.

Costco carries one or two options for a given thing, and are outright missing many things you might want. As nice as Costco is for buying things on a budget when you're going to use them up fully, I think it would be a bit of a challenge to make them your only grocery source. Doable as a sort of self-imposed challenge, no problem, there's certainly enough for that, but you'd be missing a lot of things, and/or wasting money on huge quantities of things you won't use. The quality is generally pretty decent (I may have more brand loyalty for "Kirkland" than almost any other brand) but not necessarily the most premium options. If you are the type to even consider the specialty shop in the first place you're more likely to be unsatisfied by Costco than a grocery store.

Actual specialty shops survive just fine. There's plenty of value in real expertise. Run-of-the-mill stores selling the same commodity at a higher price are simply inefficient.

The idealized small mom-and-pop shops were largely put out of business by WWII and rationing more than anything. Supermarkets and department stores have more or less been the norm in the US since long before Wal-Mart began spreading across the country.

There are still plenty of produce stands, bakeries, and butcher shops in the country. Most of what was driven out of business were small bodega-style corner stores.

99% of the reason for the mom-and-pop groceries dying out is that "our" Federal Gov't decided that it would stop bothering to enforce the law - https://en.wikipedia.org/wiki/Robinson%E2%80%93Patman_Act

And note how the modern Democratic Party - the originators of that law back in 1936 - utterly failed to give a crap about the issue.