Chinese cooking sauces in the past
Before items like soy sauce, oyster sauce, etc. were commercially produced on a large scale, where did people get them? Did they make them at home? Were there special home-businesses or shops which made these sauces in-house as a specialty, and people would go to these small businesses to purchase them? If the latter is the case, are these sauces still available in this way, and the mass produced bottles only more popular with Chinese diasporic communities? Or do people in China also use mass produced bottled products?
A look at historical re-creation reality TV would give you a pretty good idea on what people in the past did for food. Even now, in rural areas (my experience is East Asia) will have a small scale local producer for things that require fermenting (alcohol, soy sauce - type, vinegar-type condiments), time consuming processing but short shelf life products (like fresh tofu), or staples that will get the community thru a period of poor seasonal weather - be it winter or the rainy season - staples like air dried noodles, pickled veggies (most families will put up their own, but for more exotic (non-self grown), the county pickler will help stock the pantry.
FYI - the same barrels whether wood, clay, etc AND the same pickling brine is often re-used with just top-off of water and fresh vinegar or an annual straining into fresh herbs, etc from year to year and generation to generation. the famous Sichuan pickled veggies that SHOULD be freely served at any self-respecting Sichuan restaurant are often a secret family recipe, but the vinegar is from the local brewer.
If you didn't live near a seafood source, you just did not eat anything with seafood in it...
pls pls pls - read your civilization and history books! In Japan, there are still families which brew their own specialities!
and now with Organic being the craze, if you have the space and the time (fermentation takes time!), you could produce your own....just be careful to preserve and protect the purity of the bacterial starter(s)
Having watched my paternal grandmother make her own dwehnjang (Korean soy bean paste) and gochoojahng (Korean chili paste), I'm inclined to think people did make the stuff at home.
I know that some Vietnamese and Thai people still make their own fish sauce and a lot of the stuff that's sold to the locals is made in someone's home. (Granted, they're not nearly regulated as we are, for good and for bad...) So I would imagine there are lots of people in China, especially in rural areas, who buy these condiments from cottage operations.
This is a nice question but it can equally be asked of other culinary cultures--India, France, etc (with all the complications of geography and style)...Soy/Shohu has been fabricated for a long long time...and probably sold: commerce and commercial exchange of foodstuffs is not a modern idea...
A lot of Chinese sauces are reductions involving soy, rice wine, fermented vegetables..."people in China" is of course a vast general category but from my knowledge, yes, a heck of a lot of people there use mass produced products!
I'm sure some other culinary historians can add to this...
re: penthouse pup
As far as I know, most condiment type sauces were usually made by professionals. Much as European villages often had people who worked as bakers, cheesemakers and sausage makers, Asian towns would often have people or families who specialized in making thinks like soy sauce, oyster sauce etc. This actually makes sense. Soy sauce is usually desinged to be made in very large amounts, by the barrelful (well enormous jar but the idea is more or less the same), much like black bean sauce (tecnically the recipe for these two things quite similar, the difference is mainly whether at the end you puree the beans in some water and take the "juice" (soy sauce) or leave them intact.). So when you were done each of the Jars you made would be something on the order of 40-50 gallons. Even for a condiment used a regualry as soy sauce, it would be hard for a single family to use up that much soy sauce before most of it began to spoil or go off (even with it's high salt content, unpasturized soy sauce won't last forever especially once the seal on the jar has been breached (think of it like the situation a person in pre pasturization days would have had trying to drink an entire production size barrel of beer singlehanded before it went bad) . So most towns relied on a professional to make it and bought from them. I imagine that some people did make thier own, especially those in more remote and rural areas but it would by no means be the norm. Addinally some sauces required ingredients that would not be easily obtainable by everyone (especially those that required sea foods like oyster sauce or fermented shrimp) anyone who needed those and lived away from the sea basically had to let someone else make them.