For Japanese, who are accustomed to a largely uniform living standard, the double price structure in China particularly in Shanghai, which has a lot of rich people is one of a number of surprises.
Take for instance haircuts. Roadside barbers offer haircuts for 4 yuan (about ¥52)! The barbershop I patronize costs 30 yuan (about ¥390), while Metal One Shanghai's Chief Accountant pays 210 yuan (about ¥2,730). At luxury shops, a haircut can cost as much as 300 yuan (about ¥3,900).
There are roadside noodle shops that for just 3 yuan (about ¥39) will sell you a bowl of noodles of the kind that makes Japanese worry about whether they might not wreck their liver if they have such fare every day. On the other hand, expensive cafes and clothing stores that even we Japanese may hesitate to enter can be found in the Nanjin Xi Lu and Huaihai Lu areas.
Average monthly wages in Shanghai are around 2,500 yuan (about ¥32,500), but young female factory workers in the Shanghai suburbs earn monthly wages of just 500 yuan (about ¥6,500), while there are quite a few workers at large companies and foreign-affiliated companies in the middle of Shanghai who pull down 10,000 yuan (about ¥130,000) or more per month. With most households in China being dual-income families, differences between the higher and lower income households can be enormous.

China has many knockoff brand products, and Shanghai even has a knockoff brand district.
The episode that follows happened the first time I went there. A shop clerk told me to make an offer, so I responded with half the asking priced, whereupon he readily agreed. Later someone told that prices can commonly be bargained down to one third or one fourth the asking price, and I felt quite chagrined.
So when shopping in such places, don't be shy and offer a quarter of the asking price. The shop clerk may say, "You want to kill me?" or make some other melodramatic comment, but in such cases, just say, "Fine, I don't want it" and head for the exit. In most cases, the clerk will run after you, saying something like, "You're a good friend, so I'll make a special price for you." See, in China, you're a good friend from the first encounter.

Shanghai cuisine is best known for steamed dumplings and Shanghai crab dishes. There are some who complain that crab is difficult to eat, but never mind, steamed Shanghai crab is top fare. If you've not had Shanghai crab in Shanghai yet, definitely plan a business trip to Shanghai in November or December. I'll gladly let you eat my portion as I've had enough of it going out to dinner with customers every day.