You can create an account on most of the restaurant supply services and place pre-paid orders. You would be shocked at the pricing ( there would be a minimum order value as well )
I've been placing orders with a specialty restaurant supplier here in Boston, and the prices are generally equal or better than retail. Including delivery! As long as we're up for eating the minimum quantity it's a good deal.
They are comparable to Whole Foods or special store prices which are significantly higher than prices in grocery stores regular people ( read : people who don't spend $100/dinner for two and don't bat an eye ) shop.
I'm pretty price-conscious, and our household spends ~$140/person/month on groceries (with most meals eaten in the home).
Here are some things I've gotten from https://www.baldorfood.com/ in the past few weeks, including delivery:
* Bread flour at $0.46/lb
* Yeast at $4.96/lb
* Vanilla extract at $2.55/oz
* Cherry tomatoes at $1.42/pt
* Onions at $0.90/lb
* Honeycrisp apples at $1.05/lb
* Baby spinach at $4.38/lb
These are all as good or better than the Market Basket (local cheap grocery store) price, and the quality is higher. There are also many products that are fancier and more expensive than they would be at Market Basket, but I can just not buy those.
Since of those I will only buy a few items I can tell you the prices here, in NYC in a non-ethnic but non expensive supermarkets:
* Cherry tomatoes when available: $1.00/pt
* Tomatoes: $0.99-$1.50/lb, right now up to $1.69lb
* Onions: $0.59/lb
* Honey crisps: $4.99/bag ( 5lb per bag )
* Baby spinach: $2.49/lb
So the mass consumed vegetables are are about 2x the price of a local super market and they have $250 min. Try meats and fish and you see the similar level of markup.
I think their business model is to provide single point logistics services covering ingredients to companies that take those raw ingredients and do value add ( restaurants ) and selling on credit. That model does not work if there are no buyers for the logistics service.
I think should they be delivering to consumers, their competitor is instacart where the basked ends up being 20-80% higher than the same basked would be should it be filled directly in a supermarket. ( counting all the fees )
None of the examples you're listing are 2x; those are 1.4x, 1.6x, 1x, and 1.7x. The prices you're listing are also lower than what I see in the cheap grocery stores here, not sure why?
(They also are delivering to consumers; we've been putting in a weekly order and it's a way better experience than Instacart.)
Retail packaging is a pain to deal with, take for example salt. You usually buy it in small boxes, about 1-2lbs each, commercial bags are 40-50lbs. So you need to buy 20-30 boxes a week at your local store, open the boxes one by one and empty it all into your restaurant bin. It's really a convenience thing, it's much easier to handle, transport and store a single really big bag. You still buy retail for stuff that makes sense though, maybe you only need like 2lb of lemons a week to make a sauce, in that case you'd go retail.