A Computer, a Plastic Pony, and a Case of Beer - S1-E12
Question: Why does Mary grab her kids and leave just because George bought beer? I know they were fighting a little about money the night before but George used his own money, so what does it matter?
Answer: It's as simple as money is tight, it's not "George's money", it's the family's money so the expenditure was selfish.
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