Kids with Hong Kong parents but speak English as first language?

I was at McDonald the other day and saw a couple speaking to their very young daughter in English while the couple spoke perfect Cantonese to each other suggesting that like me, they are local Hong Kongers. Are they normal residence overseas and returning to Hong Kong for a vacation? I don't think so, because they are definitely not alone.

Being born and grew up in Hong Kong myself, I can "understand" why there are so many Cantonese speaking concerned parents in Hong Kong who would rather have their kids speaking English as first language. While some may say these are very international minded parents because English is for sure the most important language on the international scene both for business and general communication. However, there are also many of us who are capable of speaking multi-language at ease, so why would they need to train their kids to speak an unnatural mother-tongue?

The more I think about it, the more I feel this is very very sad. I cannot imagine anyone growing up in a Western family in his own home country would end up not speaking the mother tongue of his parents'.

So why is this happening in Hong Kong? I think the reason can be traced back to Hong Kong's colonial history.

I remember vividly, during the time when Hong Kong was still a colony of Britain, a high command of English language could certainly land you in high position, especially before 1990s. So in those days, every parents would dream of having their kids to speak good English. While this is still true, it is no longer a key differentiation because there are now so many people who can speak it fluently whether a results of better education in Hong Kong or the huge number of returnees from overseas.

Sadly this idea has extended well beyond the colonial days...

More thought:
I just met a friend who's ethically Chinese, she was born in Hong Kong with Hong Kong parents and she grew up in Sweden. Her school in Sweden encourages immigrants to learn their own language and even though she was the only Chinese in her school, they went through the trouble of finding a Chinese teacher for her. Interesting...