I've only seen one person queue jump here and that was while waiting to collect personal deposit at the entrance to Lee Plaza. The queue jumper was a foreigner. However, a few years ago on a holiday to France, seeing the Germans barge up to the front of the queue en-mass at checkout time was quite illuminating.
I have no idea. Just relaying my personal experience. Different cultures view queuing differently, evidently.
I'm not so sure if it is queue jumping or it is a mindset of, 'there is a space, fill it'. That has been my experience a few times as I was waiting in line and leaving a space for shoppers to pass by, and low and behold someone jumps in, and then I explain to them politely that the line begins back there. They smile and say sorry then go to the back of the line. That might explain the constant bumper to bumper mentality in driving, no distancing but plenty of rear end accidents.