Hong Kong is a bit easier getting used to due to a free internet, less pollution, and stricter food safety laws. But I guess there are more opportunities on the mainland.
Grad jobs in Australia offer at least the minimum wage of $40k per year. Note that I haven't seen a single job offering only $40k. The very very low end of what I've saw is $45k+. I've heard of offers of over 100k for really talented graduates.
I asked around in Hong Kong, and graduates there are only offered around HKD$15000 a month. That is only $25k per year.
I haven't mentioned the long working hours, expensive rent, and relatively expensive cost of living compared to the salary.
Top paying jobs are with international banks. You'll make pretty much the same here as you will working for them in London or NY (so, 100K+ yr, for example). From there, salaries slide to ridiculously low levels. (EDIT: it's my understanding that, due to the current economic climate in Europe, most of these banks aren't hiring).
It's a pretty bad place for any passionate programmer to end up. There's an overall lack of passion, risk is avoided at all costs, and creativity doesn't exist. It isn't just in the banks either...there's something culturally different.
I've never worked in a factory..but in my mind, it's inbetween working for a real startup and working on a factory floor. Which explains the long hours you mention...when you work 10hours every day, it's hard to be super passionate and creative.
As for cost of living. Rent is expensive. If you want to eat at a fancy $300-a-plate restaurant every night, you can (and probably a different one for many months). You can buy fancy clothes and expensive jewelry. But, if you are willing to, Hong Kong lets you live cheaply (rent aside). Remember that taxes are ~16%, with no sales tax and no capital gains taxes. If you make $150K, your take home is ~125K.
http://www.greenbacktaxservices.com/resources/blog/expat-tax...
You need to be very careful (hire a good accountant) because you don't want to owe back taxes + interest + penalties if you ever come back, but it's doable.
I've heard of people leaving Canada for 10 years, not paying any Canadian taxes...grossing millions..coming back and having the Canadian Revenue Agency (CRA) say that, in their eyes, they were always residents and having to pay 500K+ in taxes/interest/penalties. (a big part of it is how many ties you keep in Canada, if you own a house, or your wife/kids stay in Canada, those are "primary" ties, and make you a Canadian-resident for tax-purposes).
Not 7, "infinite". You can be a US citizen by birth, leave when you are a week old never to return, and owe tax on everything you earn in your lifetime above the ~$93K/yr limit.
The only way to completely avoid the US claiming taxes is to renounce your citizenship... although if you do that for economic reasons they can legally prevent you from ever visiting again (although I understand that's rarely if ever actually applied)
It's a mess if you're a US profesional with any aspirations of working abroad. On the other hand, our billionaires tend to stay put rather than fleeing to Switzerland so the policy does have its desired effect I guess.
The issues with the CRA are pretty much the same all over the world: people try to game the system by claiming they moved away while "really" living in their home country. If you make enough money away from your home tax authority expect to show some documentation. Even in the US this happens with people who claim to have moved to a low-tax state while still maintaining a residence in a different state; you need to prove you weren't within the state's borders for more than X days or the tax man will want their take. Nothing unusual about Canada in that regard.
Nevertheless, I agree it isn't bizarre or unique. The lack of a tax treaty with Hong Kong is unfortunate though. It's not even on the table from what I understand.