There're too many things that I want to put in my answer,but the most important thing that I want to tell you all is ---- GOOD / HIGH CLASS AUTHENTIC CHINESE RESTAURANT DO NOT PUT MSG IN THEIR FOOD,they use premium grade ingredients and they prepare their stocks everyday!
My dad is a good cook,my sister and I also can cook,we never put msg in our food and we buy fresh vegetables & seafood daily in the market,our meals contain lot of vegetables + fish and less meat (my family eat chicken,fresh water fish and seafood,no beef nor mutton).When we go to restaurant to have Cantonese food,the steamed fish - garoupa or lobster were killed soon after we picked from the tank.
China is a big country (as big as USA) and has the biggest population,therefore,Chinese from different regions have different cooking ways,styles & tastes.For example,Sichuan cuisine is very spicy while Cantonese cuisine isn't spicy at all.People in the north eat wheat noodles or steamed buns while people from the south eat rice or rice noodles.
Chinese food is different from Western food by the way we prepare food before cooking,Chinese cut the ingredients in bite size then stir fry or steam the ingredients in short time while westerners cook the ingredients in big pieces and cut the food on their plates with knives and forks.
There are some ingredients or seasonings in Chinese cuisine that Western cuicine seldom use,like jelly fish,sea cucumbers,shark's fins,fish maws,bird's nest,thousand years eggs,bean curds (tofu),oyster sauce,black bean sauce,salty shrimp paste,soy sauce,...etc.On the other hand,Western cooking adds herbs like rosemary,dill,sage,oregano,thyme,tarragon..etc,in their food while seldom you would find these herbs in Chinese food.Chinese add ginger,spring onions,mints,corianders,white pepper ...,you hardly can find any traditional Chinese food contains cheese,butter,cream or milk