Wow, this thread makes it sound like BFing in HK is horrible!
You are in fact legally entitled to BF in public here. But as other posters have said, Chinese people seem to be shy about it.
I've never had any problems and still regularly BF my 6 month old in public.
I find Starbucks, Pacific Coffee, hotel lobbies, to be very comfortable. And there are plenty of them around.
Don't feel pressured to cover up either. I don't, and I've found that most people don't even give you a second glance.