I was nice enough to hold the door open for a Japanese guy one day and he decided to remind me of Pearl Harbor. "Sank you". Asshole.
Are you saying that all Japanese people aren't nice?
It turns out he is a little red dot with offensive eyes, I mean look at those glasses. He's one of those that chant about a rising sun and were angry about their defeat in the war.
It can be upsetting to be attacked when you are trying to be nice but it is not good to make fun of another person for their accent. You would not like it if you visited another country and the people there made fun of your American accent.