Fair question! And I feel like this is something that an anthropologist or a psychologist would be better positioned to answer, tbh. But anecdotally, as an insider to US culture, I feel like the culture's hyper-focus on the value and impact of the individual can take either course, depending on the underlying character of the person involved.
Yes, some people behave the way they behave simply because they're afraid of consequences. Anywhere in the world.
But some people behave the way they behave because they have a heightened sense of empathy for others' rights and needs — and in a culture where The Individual is weighted so heavily, I suspect that this empathy takes on an added dimension: that naturally empathic person carries an even stronger sense of responsibility towards others, because the person recognizes the real difference that one individual can make. (I.e., they see themselves not as "one among a herd" but a player capable of creating real positive or negative change.)
We could conjecture that this lady was afraid of the trouble she'd face for inconveniencing others, but arguably, the trouble of missing a flight is even larger. If she were truly, strictly utilitarian about her choices and only focused on wanting to avoid a negative consequence, then waiting in the line made the lesser amount of sense. So I do imagine there was some level of respect at play there, rather than just fear of reprimand.
That said, there was recently an interesting piece in Le Monde about individualization vs. individualism, and how we often misuse these words. I've probably misused them myself. ;) Unfortunately, I wasn't able to read the whole thing (paywalled), but the analysis explained that individualization — a quest for and a prioritization of greater autonomy — actually correlates with a lot of healthy, socially cohesive values, like being more open to "outsiders," more progressive, etc. Meanwhile, individualism, it explains, is about withdrawal from the broader society and its concerns. That's a pretty important difference. Link here in case you're curious! :)
