I too have witnessed this in Bali, Peru, and Costa Rica, and can only attribute it to a power in numbers cultural thing. It’s the same on tour, aside from dark horse Caio, pretty much all the Brazilians travel with a cadre that is there to comfort them like emotional support animals.
In your experience are there groups of Japanese as well? They are a group based culture so it would make sense, yet surfing is kind of a subculture so they may not have as strong a presence.
I’ve copped packs of Israeli’s whilst travelling in Mainland Mexico. Apparently, they can’t go to Indonesia due to them being a Jewish country (my facts could be wrong), but the clog lineups, don’t know ettiquette and rarely even use manners when speaking on land!