The main reason HKPA should not be included in pay offers, just like housing. Both should be negotiated as separate issues. Only those eligible for the benefit should be allowed to vote on said benefit. Lumping in HKPA with pay is setting a precedent and housing will follow.
Any pay deal with either HKPA or housing should be instantly thrown out.
The time will come when an increase to HKPA and a decrease in housing are voted for in the same motion by all members.