It was partly that emotions were heightened as it was, knowing that Vietnam was falling and knowing all those people would be coming in to the camps.
Most of the refugees were very nice. The exception was the high-echelon refugees (generals, senior government officials). They were all housed in their own separate VIP camp. I partly volunteered at the refugee PX tent or whatever its called in the Marines, and those guys could be real jerks when they came in and simply ordered you to give them everything.
One time they had a Marine Corps protocol officer with them. He was dressed in a suit but you could tell he was a Marine because he had a Marine tie and tie bar on. The Vietnamese started being really obnoxious and the volunteers started getting upset. The poor protocol officer who was standing behind them kept on trying to motion to us with his hands to stay calm and he was silently mouthing “just do what they want.”
A lot of the blame for losing the war falls squarely on the shoulder of the Government of South Vietnam, who favored the Catholic minority, and alienated the Buddhist majority of the South.