Trivia: Zoe Perry, who plays Sheldon's mother Mary, is the daughter of Laurie Metcalf, who plays Mary on The Big Bang Theory.
Trivia: Sheldon's dad, George Sr, is played by Lance Barber. Barber appeared in an episode of "The Big Bang Theory" as a former bully of Leonard, Jimmy Speckerman. Sheldon (and the gang) go with Leonard to meet Jimmy.
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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