Some of those sound fair enough.
I've rebooted a production server once or twice by accident during high pressure events, and once or twice when a patch documented as not requiring a reboot suddenly crashed a component and/or forced a reboot. I came clean immediately but the impact was minimal so no damage done.
You have to wonder though. When a company can't afford high availability, and doesn't use VMs so there's no machine-level backups and restore for testing (a WTF in itself), what does it expect? I'm not talking about being cavalier, but due care does not extend to never doing anything because of the small risks involved. You reduce risks by being aware but they never reach 0 (excluding financial systems, health, aviation, the military, etc).
But you know, firing those people only ends up with retaining the workers who refuse to so much as blink without multiple layers of documented posterior covers, and the infrastructure that the company didn't want to invest in in the first place. Consequently, the company is the only one to suffer by acting rashly.
I'm going to throw one more possibility into the mix though. An employee refusing an order. Not every order, many orders, or any order, but an order; claiming it is either impossible, risky, unethical, or technically unsound.
In my mind (and probably only mine!) as an employee I see the contract as a way to provide full-time technical services to a company, but that contract immediately stops at the line where I'm ordered to do something where I would be unable to sleep at night. These events are few and far between but they have happened once or twice over the decade.
In most cases when I discuss it with colleagues I hear the same response: do it under protest, the documentation will cover you.
But I don't feel that way. I feel that ultimately, just like having a gun put in your hand, if someone orders you to shoot then it's still your fault for deciding to pull the trigger. "I was forced!" Yeah, but you'll still be out of a job either way. Now which way do you want to go, with your ethics and self worth (which is lost by violating your ethics), or without them?
To put it another way, would you do something terrible, just so you could turn around and tell your employer, "See! I told you so!" I suspect that would be an unprofessional attitude. So why is towing the line against all your best judgement seen as ethical?
In some cases the company realizes, hey this person is ready to get fired for refusal and so maybe they have a damned good reason, and in other cases it was their way or the highway and I choose the highway. To me, my technical expertise is for sale, but not my self worth. Not for any price. I'd accept being fired from that situation, though, I'm more likely to just hand in my resignation. Even at that point, some companies still feel they can make demands and that they must be followed during your notice period. I definitely don't agree with that.