Don't HKU interview their candidates online too?
Anyway, my point is that their requirement might not be able to attract candidates with the most potential and talent because people with amazing grades like A*A*A would more likely go to a top law school in the UK or the US rather than HKU.
Say there are two groups of students. One group who got the grades A*A*A or better will probably go to the universities in the golden triangle. The other group with lower grades (say, A*AA), though almost equally intelligent and hard working, will be immediately put off applying because of the minimum requirement.
But I mean for people who would like to practice in Hong Kong, studying an LLB degree at HKU might be the most straightforward way anyway.