It comes from several reasons. Back in college before it was en vogue, I read a ton of books on China...and have a lot more that I haven't read since then, literally about 15-20 books.
Also, if you look at how the Chinese is trying to ingratiate itself with Africans using a slogan of "together the Chinese and African can defeat the West"....using a " You can trust us we're not white" theme. I believe that the Chinese should be watched with a decerning eye, due to this maybe the second raping of Africa.
And, if you visit any Chinese websites, they tend to have this mentality of the kid who just inherited millions of dollars...brash, arrogant, insolent, and full of oneself.
Yes - a good part of my family is as your describe.
One thing few people in the west understand, is that the Chinese have a very different concept of time. I remember my grandmother telling me that Japan would pay for their war crimes (and her husband was Japanese!). I was young at the time but even then, when she started saying '100 years, 400 years, doesn't matter. China will make them bow down", I was surprised.
Look at what China has done to Tibet. Send in some workers first (well, in this case after the military). Pay them well so that they'll stay. Send in some more. Start to infiltrate the local population. Slowly introduce more and more aspects of chinese culture (even if it takes a few generations). Eventually, you have a place that once upon a time wasn't Chinese, but now is.
Same thing is happening now in Burma with all the road builders. They're not going home and more and more are moving in.
Same thing will happen in Africa. That's where their world domination will start and it won't look like much (because it's Africa), but it's just a stepping stone, and with such a long term perspective, it'll only be a small piece of the puzzle for them.