First of, there is no plural form of youth. It is both singular and plural. Depends on the usage. Smart-ass! aren't I?

But getting back to your Nepali Youth being rowdy question/concern. You see more of such behavior in Nepal and not much of it in the United States. But they do loiter around at the ANA hotel lobby, the entrance, and the corridors even while the front desk staff will naturally be wishing that they would stop doing that. Gotta love Nepal
and Nepalese!