Where I live there is Coles and Woolworths plus IGA and Foodland. The others spoken of in this thread do not exist here.
We shop at Woolies because I think it is cheapest and also has a good range of product. It is also the biggest store in the district. We bought a 10kg bag of Home Brand long grain white rice there last week for $10. It was Product of Thailand and the quality is OK. Given current high world rice prices I think our bag was good value for money.