I have a friend who 'shops' the whole country from Ha Tien right up to Langson and all points in between. When I say shops, he records the prices (with a discrete scanner) and he sends them off to hos employer and they then sell the data on.
CO-OP MART
You must be a relative newcomer to VietNam as you would know about Co-Op Mart, aka SaiGon Co-Op, owned by the city for the benefit of the residents.
YOU SAID: Anything but economical let me assure you (Co-Op). OBVIOUSLY you haven't shopped around as Co-Op Mart prices are amongst the best in VietNam. It is also the biggest. It has it's own buyers that deal with manufacturers.
Who else has their own branded noodles at prices as low as VND2,200? Who else has stores up and down the country? Whose sole function is to help Vietnamese get quality food at low prices.
DO YOU HAVE A CO-OP AFFINITY CARD? Affinity cards reduce prices significantly.
The affinity card makes a big difference. Last year, when profits were low because of high food prices, I still got several millions in rebates AND they have give-aways of china, raincoats, etc.
SaiGon Mart/Co-Op Mart also whoiesales to other supermarkets.
METRO MART
Metro is a WHOLESALE supplier from Germany who now allow retail shoppers in. IF you qualify for a TRADE card (TAX number required) you will see substantial discounts off sticker prices. If you only qualify for a RETAIL card you will see some discounting dependent on the prices.
Many supermarkets buy from Metro - which means Metro prices must be better.
Metro sells everything (at least in VietNam) and is more like a box store in the States or Canadian Tire in Canada (with food added)
LOTTE MART
Korean owned, and has an AFFINITY CARD. These days, unless you are after Japanese and Korean foodstuffs the prices are way too high.
GIANTS SUPERMARKET (Crescent Mall)
This Malaysian owned supermarket is over-priced. It has NO AFFINITY CARD.
What it is good for are a wide selection of Western (American) sauces/convenience products - BBQ ribs flavour sources, good selection of Olive Oils and many imported brands (for which youy pay dearly for)
VAT Tax
Many Foreigners don't realise some food products are subject to VAT TAX, which increases the price by 10%.
MY WIFE'S BUYING STRATEGY
Co-Op Mart for all basic food shopping; Metro Mart for limited purchases including meat; GIANTS for speciality sauces and olive oil.
Vegetables from a trusted retailer at a MARKET with whom you have a long term relationship. My offices are in Quan 7 (and our short-term living quarters) so I do all veggie and FISH shopping at the CHO TAN MY (Nguyen Thi Tap@Nguyen Van Linh) which has good enough quality even for some Phu My Hung types who thinking overpaying shows class.
I use one veggie retailer who has remembered what I buy and she points to each item and I simply signal how many kilos I want. As some market dealers occasionally have better products (tomatoes) I use them, too.
Buying fish is easy. But you need a list. I don't eat anything from 'fresh' water (think SaiGon River and pollution). So you need a list of sea fish. I only buy fish that are alive and jumping - then I have the fishmonger prepare / dress the fish so it is pan ready.
The benefits from buying outside Quan 1 and 3 is that Foreigners don't get ripped off - you pay VN prices.
There are 24/7 bakeries, flower shop, food stands at TAN MY MARKET - guaranteed fresh.
MEAT
Halal stores airfreight meat (beef, lamb, chicken, etc) direct from Australia and New Zealand. There is a posting about where to buy Halal meat if you search for it. There is some American meat which is OK if you like GM
IMPORTED FOOD/FOREIGN FOOD
You pay dearly for imported food - a can of Campbells concentrated soup for $2.50? Ditto for Nestle products, etc.
So live 'local'. If you are a Knorr soup user, try S-COOK at a fraction of the price and no artificial junk; if you like a particular flavour of coffee take a sample to a decent coffee store (Ham Nghi Street in Q1) and have them blend a kilo or two for you. There are even better blenders in Cho Lon.
I like 'Brazilian' flavoured coffee - and I get my VN Brazilian from Hong Vuong and Ta Uyen area.
'ORGANIC' FOOD
The USA, and a few other countries, have established standards the make food organic. Little, if any food, in VietNam, can be classified as 'organic'.
The stores do have better quality (appearance) products but most get their supplies from the Binh Chanh wholesale vegetable market. Most of the veggies in TP HCM come from Da Lat - soi claims about Da Lat can be forgotten - they are the same as everyone else.
A couple of HCM stores claim 'from our farm' - get the address and you will see the farm sells to anyone - the label 'Organic' appearing en route from Da Lat.
But don't go saying "Anything but economical let me assure you (Co-Op Mart)", it shows your lack of knowledge.
Update:
As of last Friday the difference between Co-Op Mart retail price and Vinamilk distributor wholesale price was 2,355. Imported milk sells for VND20,000-30,000 more.