Emotions are not reasonable nor rational. When people are stressed, they lash out inappropriately. This can take many forms, including being abusive to customers.
It does not mean the person is simply "A dick". It means that they are behaving like a dick, to people who are perceived to be related to the source of their stress.
The real source of the stress is the management of the package delivery company, making ever more absurd demands of delivery personnel, in tight holiday timeschedules, forcing them to give up their holiday while "these people insist on having shit delivered more and more. "
It is still ultimately the management that is at fault; Customers will make utility of any offering provided to them. That is the nature of customer interaction. Most customers do not contemplate whether or not something SHOULD be possible, or what the consequences of that service being available actually are. This is in part, due to the actions of the management behind those service, who WANT the customers to feel comfortable using (and abusing) them, because that is how they get market share, and make money.
The ones being self-serving, money minded, and shamelessly psychopathic dill-holes are management; not the end customers. However, management is untouchable. The customers however? You can fuck with them, by abusing and mistreating their packages. (with the thought that maybe, "if enough packages are ruined in the holidays, maybe they will stop having everything fucking shipped then, Hmm?")
Its a curious thing--- You squeeze that last little bit of humanity out of people, and they stop acting with human dignity or decorum. What an amazing concept. /s
The "solution", as far as the management of these delivery companies is concerned though, is divided between "We'll replace them all with robots", and or "We will fire them when they finally turn into ravenous blood thirsty murderers-to-be, by abusing our unfair market position thanks to At-Will employment laws."
Really, you should not have packages delivered during holidays unless you absolutely have to. In my case, the package was international, and *FUCKING SAT IN CUSTOMS FOR A MONTH*, and it happening to get shipped during christmas was not my doing nor my intent; I would not have done that knowingly. These days though, rather than go actually shopping earlier in the year and then hiding presents (like used to happen) people get everything from Amazon and pals like, the day before christmas, then wrap everything in a hurry. This has real consequences on the people who already suffer in the package mines of mordor--- er... Amazon warehouses.
So, I get it that package handlers are burnt-out, and tired. Where I disagree is with destroying or mistreating packages; The correct course of action is lighting torches and brandishing pitch-forks at your legislature, so that they fucking fix the unfair circumstances at work in the employment front, and working conditions improve.