5. Soy Sauce Usage
I'm not sure how widespread this is, but in the UK, many if not most Chinese restaurants have a bottle of soy sauce on each table, alongside salt and pepper, allowing the dinner to adjust the taste to their satisfaction. In China, soy sauce is only used in the kitchen (with one exception which I'll get to). I've often eaten in Chinese homes, and never seen soy sauce near a table. Or salt and pepper.
This very amusing clip from The Joy Luck Club is flawed in that there would never have been that bottle of soy sauce on the table, which is the climax of the joke.
The exception I mentioned is in places selling jiaozi or other items requiring a dip. There will usually be a separate table or counter with soy sauce, vinegar, chilli, garlic coriander/cilantro, chopped Chinese chives etc for the customers to construct their preferred dip.
Alternatively the dips may be pre-prepared by the kitchen.