Look at Vietnamese photos of cities and you will see big stores, both domestic and from other countries. But these are new developments. Like China (where I live) Vietnam has always had many street vendors and small stores. Even in the big cities you still see these, and in towns and villages almost every store is a small shop.
On the left here you see a typical street vendor in Vietnam. In this
case the lady is selling a toy - apparently some bobbing birds. Street
vendors sell an amazing variety of things.
You see a lot of vendors in public parks, often selling snacks or souvenirs. There are fixed stands for this too but usually you'll see many people like these ladies selling stuff.
The small family store
is another thing commonly seen throughout Vietnam. Here's a store that
seems to sell both stuffed toys and propane. OK, maybe the toys are in
the shop beside but don't you like the cute
pink and blue colour schemes for the gas tanks? Don't they kind of go
with a stuffed toy theme?
Here you see some ladies setting up along a Vietnamese street to sell fruit. One thing to note here is the "squat". I've always found it amazing how the Chinese who live around me can just squat down on their heels and not only be balanced, but comfortable! This picture shows that Vietnamese people do that too.
Here you see a whole row of fruit sellers along a road. This motorcycle looks kind of overloaded but look at enough Vietnamese photos and you'll realize that it isn't by Vietnamese standards.
Where we in the West would expect to see a truck, small-scale places in Vietnam use whatever vehicle is available - which is usually a small motorcyle.
In China the use of motorcycles and scooters has mushroomed since 2005 or so, though there are still a lot of 3-wheel pedal carts for local delivery of goods. Vietnam was ahead of China in this aspect. Vietnamese roads have been full of small motorcycles since the 1990s.
Arriving at the market, it's time to unload the carcass of a pig that was rooting around in some farmer's yard a few hours before. Food in Asian street markets like this is fresh...
...but maybe not so sanitary. Here's a not-unusual meat market in Vietnam. The meat just sits out like this throughout the day. If that doesn't sound healthy to you, you're right, but meat is sold this way in many Asian countries' free markets including my host country China.
In the early 1990s a lady who was health inspector trainer in Germany visited my university in China. She counted herself fortunate to get a tour of the kitchen of one of our cafeterias, but came back shaking her head. She said (and this is almost a direct quote) that the only reason anybody was still alive around there was that the meat was cut in small pieces and cooked on high heat. In general, Asian cooking is done like this, which is why butcher's stands like the one above do fine there.
This stall is part of a larger market that includes what looks like eating tables at the back. Free markets like these give a family a chance to run a business in a popular location with only a moderate rent cost.
These Vietnamese photos of markets have given you just a taste of the vendors, small stores, and markets you can see in modern Vietnam.