This was not always the case. 30 years ago the customer base for bulk co-op places were lower-middle class/poor folks who had a decent amount of financial acumen. You'd go there with your own containers and buy staples by the pound. Or special order that 50lb bag of oats or flour for 1/4th the per-lb price of the local grocery store.
They slowly morphed into bougie health nut/conspiracy hippie stores during my lifetime. Closest thing I've found to what I remember them being are food service stores which tend to require a business tax ID to buy from.
Davis Co-op c. 2000 was legit cheap and good. I lived across the street from it for some time.
I can do without the "health/wellness" aisle of mystery fluid bottles almost entirely. Whole Paycheck Foods and a lot of independent grocers also have this fad and it's depressing that borderline Miracle Mineral Solution nonsense is allowed through under-regulated "supplement" exceptions. More power to those who benefit from ever-so-slightly-helpful / placebo vitamins-supplements but it seems like mostly from snake oil of a century ago.
Anyhow, there are/were more decent grocers. Like Lundari's 30 years ago in the SF Bay Area. The status quo isn't the only available option.
And we need more local co-op grocery stores like Berkeley Bowl, the Davis Co-op, and ATX Wheatsville.