Yes, people naturally develop pre-emptive defense mechanisms to lower the impact of the ornery members of the public. This kicks off a self-reinforcing downwar

Yes, people naturally develop pre-emptive defense mechanisms to lower the impact of the ornery members of the public. This kicks off a self-reinforcing downward spiral where people with innocuous intent are misclassified and treated tersely, that party responds by iterating to a less polite/more direct posture the next time, which reinforces the original party's assumptions, which eventually degrade into general hostility, which loops back around to inform the other party that he needs to be even less polite to get what he wants the next time... However, it is probably the case that those lower 5% actually are so potentially damaging that imposing strict preventative policies to inhibit them is legitimately worthwhile, despite the negative impact on everyone else. Airport security is a potentially good example. Yes, there are many ways to bypass it. Yes, it is very annoying. Yes, it creates other liabilities that are arguably more exploitable in the absolute sense. But the bottom rung of civilization is not sophisticated. They are looking for the path of least resistance, and putting some basic barriers in the way may well put disruptive/negative behaviors outside of their reach. Most people who are smart enough to bypass airport security would not see the incentive in doing so. From the policy/standard perspective, that's the barrier that has to be established; the cost has to be sufficient to exclude people who would be doing it out of insanity or other generalized anti-social malice. It'd be interesting to see some discussion of methods to limit human "interaction fatigue" in the context of the modern service professional, and how we can simultaneously implement policies and protocols to protect ourselves from the insane, unstable, and truly incompetent.