This arose from this topic, where initially @Anna N asked about tea not being served at the celebratory meal I attended. I answered that it is uncommon for tea to be served with meals (with one major exception). I was then asked for further elucidation by @Smithy. I did start replying on the topic but the answer got longer than I anticipated and was getting away from the originally intended topic about one specific meal. So here were are..
I'd say there are four components to tea drinking in China.
a) When you arrive at a restaurant, you are often given a pot of tea which people will sip while contemplating the menu and waiting for other guests to arrive. Dining out is very much a group activity, in the main. When everyone is there and the food dishes start to arrive the tea is nearly always forgotten about. The tea served like this will often be a fairly cheap, common brand - usually green.
You also may be given a cup of tea in a shop if your purchase is a complicated one. I recently bought a new lap top and the shop assistant handed me tea to sip as she took down the details of my requirements. Also, I recently had my eyes re-tested in order to get new spectacles. Again, a cup of tea was provided. Visit someone in an office or have a formal meeting and tea or water will be provided.
b) You see people walking about with large flasks (not necessarily vacuum flasks) of tea which they sip during the day to rehydrate themselves. Taxi drivers, bus drivers, shop keepers etc all have their tea flask. Of course, the tea goes cold. I have a vacuum flask, but seldom use it - not a big tea fan. There are shops just dedicated to selling the drinks flasks.
c) There has been a recent fashion for milk tea and bubble tea here, two trends imported from Hong Kong and Taiwan respectively. It is sold from kiosks and mainly attracts younger customers. McDonald's and KFC both do milk and bubble teas.
Bubble and Milk Tea Stall
And another - there are hundreds of them around!
McDonald's Ice Cream and Drinks Kiosk.
McDonald's Milk Tea Ad
d) There are very formal tea tastings and tea ceremonies, similar in many ways to western wine tastings. These usually take place in tea houses where you can sample teas and purchase the tea for home use. These places can be expensive and some rare teas attract staggering prices. The places doing this pride themselves on preparing the tea perfectly and have their special rituals. I've been a few times, usually with friends, but it's not really my thing. Below is one of the oldest serious tea houses in the city. As you can see, they don't go out of their way to attract custom. Their name implies they are an educational service as much as anything else. Very expensive!
Supermarkets and corner shops carry very little tea. This is the entire tea shelving in my local supermarket. Mostly locally grown green tea.
Local Guangxi Tea
The most expensive in the supermarket was this Pu-er Tea (普洱茶 pǔ ěr chá) from Yunnan province. It works out at ¥0.32per gram as opposed to ¥0.08 for the local stuff. However, in the tea houses, prices can go much, much higher!