How to respond to the teacher who puts the feet up while talking to student? A friend of mine who is from Japan told me that his professor in USA puts the feet up while talking to him. He was saying that he felt very bad with that. Is this acceptable culture in USA academia?
I've done my PhD in Japan, and have had much contact with professors in America and Japan.

The academic relationship and work culture in both countries are very different. In America it is generally not regarded as bad when someone puts their feet on the table while talking to you.

I had bosses and advisors in the US who did this. However, in Japan, the advisor-student relationship is more respectful and professional. 

I would like to tell you that you should ask the professor to refrain from putting their feet on the table, but if they do it in their office, it is pretty much up to them. Since the office is the professor's space, I do not think it is your friend's business to ask them not to do it.