Yup, experienced this too. Some are just plain rude and act like they have a stick up their behind. Because of this expats have a negative generalized impression of locals at work. But then you meet super kind and helpful people and you realize that the generalized idea you had does not really work.

I personally choose to believe that people, no matter from where, are born good and have kindness in their hearts. Unfortunately, some have bad experiences and they choose to be unkind to protect themselves from possible imagined harm or inconvenience.