As others said, do not blame the security guards, they are only doing what they are told to do.
Regretfully, they do seem to stop mainly Asian males. Regretfully again, it is not due to reaching their capacity. Villagio are not safety minded in the least. I believe they have two reasons for carrying out the same (not that I agree with throwing people in a bucket so to speak).

1. Assuming that the men they are rejecting entry are not going to spend money but walk around.
2. Assuming that too many bachelors considered to be "junior staff" is not desirable for their mall ambience and lady patrons.....

Again, one should avoid such stereo type systems, but we all endure it from time to time...and might even have done the same too out of frustration or for other reasons.

Personally, I believe that any mall has the right to prevent bachelors from entering if they have a family day. Although I can imagine it being a pain in the neck for men...if that is the system within this society, then so be it.... No family day formally noted should mean that everyone should be permitted access and only removed if he/she has caused an issue of some sort.