Immigrants Don't Like You to Imitate Their Accent

People don't like you to mimic their accent. What's your opinion about it? For example, if an immigrant says, get a mate, how it is understood that he wants to use it as a ridiculous sentence? I think this is the kind of thing where imigrants would have the upper hand and would probably come across as more friendly by doing this than if it were an american or a british person,. A canadian or a new zealander or someone else who's a native english speaker. So i wouldn't straightway be offended but i would probably be thinking, is ye making fun of me?