Q4. Is it legal for taxi drivers to give discounts on fares?
Generally speaking, it is legal. There is no provisions under the Road Traffic (Public Service Vehicles) Regulations (Cap. 374D) prohibiting taxi drivers from charging lower than scale of fees specified under Schedule 5 of the Road Traffic (Public Service Vehicles) Regulations (Cap. 374D).
No soliciting
However, if the driver of taxi uses discount as a means to solicit intending passengers to take that taxi, that may constitute soliciting and would contravene Regulation 40 of the Road Traffic (Public Service Vehicles) Regulations (Cap. 374D), which provides that no driver or person acting or purporting to act on behalf of the driver of a taxi, shall in any manner attract or endeavour to attract any person in order to induce such person to make use of the vehicle.
Any person who without reasonable excuse contravenes Regulation 40 commits an offence and is liable on conviction to a fine at HK$10,000 and to imprisonment for 6 months: see Regulation 57(4) of the Road Traffic (Public Service Vehicles) Regulations (Cap. 374D).