Pyjama in winter? Luch time?…normal in Shanghai

Sounds incredible, In Shanghai, some parts of Shanghai its normal. Ok in the morning and evening, why not, it could be acceptable but when you meet ppl who have pyjama in the middle of day, at the street in restaurant or supermarket,…foreigners start to thin about it. Neither our friends from Shanghai dont know why is it. When we asked we got 3 different answears:

1.they dont want to change their clothes and when they wake up or before they go to sleep, they need something so they dont care about clothes…-but in the middle of day?

2. they want to show to everyone that they have enought money, they dont have need to go to work and that they can rest whole day

3. they dont care about fashion, they wear what is cheap and comfortable for hem.

Now, when its freezing in Shnaghai, there are also warm pyjamas !!! It seems really cool. I started to think about buy one. It seem really good J In pyjamas you can meet ppl in all ages, so sometimes its fun. Meet them in restaurant or in supermarket.
If someone of you have idea why is it so let me know.