From my point of view, your advisor must treat you like a very close friend so she directly pointed what she wanted to say. If you are a close/best friend of your friends in Taiwan, it is necessary to point out the disadvantages of your friends. If your friends cannot accept what you say, that means they do not treat you as a close friend as you do to them. Therefore, from this point, your Taiwanese friends will ask about your salary, but if you don't think they are your close friends, just give them a very vague answer.
I really don't get your point here so I cannot provide my exact viewpoint. However, I guess that your friends want to point out something which is quite painful to you(something more painful than you look fatter). So they cannot just directly tell you what they want to say. They are afraid that you will get hurt. Moreover, Taiwanese will tell you what they thnk you want to hear because they think they know you(this means they treat you as a close friend), but if you don't agree with them, just ignore what they say in silence.
Cultures are the complicated things wherever you are.
All the best,
Colin