Oh well yes the concept of a queue or a line in Asia seems to be not a thing. Especially if you're standing and giving a small amount of personal space to the person in front of you. They take that as an invitation to cut in. On the other hand, typically the cultures are non-confrontational so as a person from the US I just get loud and be like what the fuck are you doing. They realize their mistake and sheepishly moved to the back.
Very much a different cultural concept because most of the time no one else will say anything they just deal with it. I think in the US if you cut in line you might get shot or at minimum start some sort of physical altercation. And people just generally know this so they don't do it.