Not really a surprise. It's the same story elsewhere around the world. They had to adapt to survive. They firstly adapted local ingredients with techniques and flavours of home to cater to their fellow migrants, then they'd start adding some new dishes based on what they perceived as local tastes to try to attract the "native" population when just catering to their fellow migrants wasn't enough to survive.

How close a restaurants' dishes are to "authentic" ones depends largely on how many generations removed the chef is from their homeland.

Anyway, I'm of Chinese descent. First generation in my family born in Australia, but several more removed from China. So while the food that my family cooks retains Chineseness it also contains influences from the countries that my parents grew up in mixed in with ingredients that were sourceble in Melbourne, Australia in the 80s. That said, due to the relative distance of Australia to Asia during the mid to late 90s, more ingredients came in as the post-Vietnam war migrants settled here and had become further established in the community (so had capital to spend on luxuries like imported ingredients).

Some links that may be of interest: - http://www.abc.net.au/news/2016-02-21/humble-chinese-diner-m... - http://www.chia.chinesemuseum.com.au/biogs/CH01148b.htm - Chifa (Chinese Peruvian Cuisine) https://immigrationtalk.org/2013/07/17/chifa-the-story-behin... - https://en.wikipedia.org/wiki/Caribbean_Chinese_cuisine