OK I think I've found the answer for this. You used to be able to enjoy 30 minutes of free parking every three hours at HKG. They've now tightened it down to just once per day. So depending on whether the driver's already used up his daily allowance, he may want to meet you outside of the car park:

https://web.archive.org/web/20230605...g-charges.page
https://www.hongkongairport.com/en/t...g-charges.page