Mad Mimm, Your post is filled with wisdom.
This would have bothered me for a very short time, I'd have given a thought or two to 'revenge', then decided it wasn't worth the effort.
I also think about an acquaintance of mine who moaned and groaned about the $1 gift her MIL gave her for the holidays or birthdays after scouring stores for weeks for just the right thing. She followed that up with the information that her MIL had been in a concentration camp during WWII. That explained her MIL behavior to me; she had learned a very hard lesson about survival and resources and could not forget it, not even for a minute. Sadly, it didn't help my acquaintance 'get' her MIL.