There are exceptional cases, detrimental to both you and the company. Company already swallowed a pretty serious loss, in that case arguably common sense is to let it go, sometimes sh*t happens.
No. We insure ourselves against unforeseen events whose effects are financially unbearable to us otherwise. You've conveniently carved out certain unforeseen events in order to serve your point rather than being intellectually honest.
Businesses insure themselves against the death of an important employee, for example. If that employee is murdered, that is neither an act of nature, an accident, nor thievery.
You might argue "you were robbed of an employee" and stretch the meaning of the word "thief" but then I'd say a similar stretching of "act of nature [or] accident" includes "aircraft malfunction"
Businesses also insure against a great many other things.
The airline itself should insure against such events, or rather what follows from them.
I was referring to the case when an engine went bad and company had to use intermediate airport and accomodate all users for the night. Also you wouldn't want to punish company hard for admiting technical issues, since that might cause them to underreport and create dangerous situations.