The only thing they care is where they can buy some discounted clothes. You see, according to my personal experience, when they want to share something with you, that means ---------all most, they want to take advantage now, be careful! They know nothing about polite . As we are in Uk, no dilect should show off when ever there are foreighers or those who can not understand your language around . Not only me, actually, students from Guangdong, Beijing etc. feel all the same. I know there are some good shanghai ren , but not those students in wales , at least not all of them.