When a relationship gets serious, one of the trickiest things about it can be surviving the introduction to your significant other's family. You've got to somehow pass the test of acceptability based on standards and values that you may only know basic information about.
This is something that many try and fail at. Sometimes, the reasons for this are understandable and other times, they appear to be nothing short of ridiculous.
One Redditor had an altercation that fell into the latter category recently, after paying for a meal after he went out with his fiancé and her family on the agreement that they would cover the tip. After learning that they had only left $1, he told them that he did not want to pay for their food again. While his future family-in-law took great offence to this, the people of AITA were solidly on his side. These things are a two-way street.