[Psychlist]

I buy rice in 25kg sacks just like the bulk buy places do. And a bunch of other stuff from a wholesale outlet that sells larger containers.

Our local food co-ops buy most of their stuff in 20kg or bigger containers. One even managed to get a 200 litre drum of concentrated dishwashing liquid.

Warning: after some discussion with members we dilute the concentrate two parts water to one part concentrate because buyers mostly dilute it ~the same again or just "use less". When we tested the "use less" people we found they used about half... the stuff is approx 10x the concentration of normal dishwashing liquid. Use a spray bottle that you bought full of something else for dishwashing liquid. It's very convenient and you can dilute it to suit what people in your house actually do.