You do not get paid during training. You get some allowances which I assume would be enough for a few beers at the weekend but accommodation and meals are all included.
As above cadets and direct entry are on the same salary. Cadets do not get housing allowance which is about 60K HK$ a month at the moment. You do not pay anything for training, the company get their money back many times over during your career with them. In fact if you locked in at the top it was HK$74,000 a month in 2008 at one point so for the 15 years you get housing they save HK$13,320,000 that is if you decide not to rent before paying off a mortgage or using all 15 years. So yeah you do have to pay for the training I guess.