most of cabin crews enjoyed mobile Internet in front of gate 32 during waiting for embarking
What do you expect them to do? As long as they were sitting there, and not disturbing anyone else, then what's the problem.
They're not there to look after you in the terminal, that's the ground staff's job.
Cathay, in their wisdom, don't even pay the new "hourly crew" the full hourly rate until departure, so during the pre-flight, they're only working for 50% of their published salary scale. They're getting paid $0 per hour whilst waiting in the terminal like that, so what do you expect.
(Note: That's HK$0/hr. As exchange rates fluctuate, I'll allow you to look up the exchange rate, and convert to whatever currency you use in your daily life)