It may be related, but TG also used to ask for the HK ID. (I'm not Chinese, but do hold a HKID card). A few times I told them I didn't have a HKID (just to see what they said) then of course they had to get the Supervisor etc etc. Never got a convincing reason why. (and IMHO a very bad thing to ask someone for at a 7am check in!!)
There is no reason why they should have to see a HKID, e.g. even if flying on a one-way (or return leg) you could be heading on up into China...
BTW, most HK hotels have special rates or packages for HKID card holders. They first (?) started during the economic downturn a year or two back and many have continued them. Good for returning ID card holders, or folks here in HK who want a weekend away..
As for special fares ex. HKG - these are available to anyone; you just walk into a travel agent, book it, pay for it and go.
And on a final note, for any of you heading this way, I see the HK-Macau helicopter service is doing special fares (one way, must book in advance) for 500something HKD one way (this is about 1/2 price from memory). Anyone want the contact, drop me a line...
[This message has been edited by Eric the half a bee (edited 05-14-2001).]