A Broom Closet and Satan's Monopoly Board - S3-E2
Continuity mistake: George invites Mary out to dinner on Friday. But while they are at dinner, Sheldon is attending his college class (with Dr. Linkletter) - which meets on Thursday.
A Baby Tooth and the Egyptian God of Knowledge - S3-E20
Factual error: Georgie removes his stash of cash from the air vent in his bedroom (envelope with a photo of a mustang taped to it) and the cash ($20 bills) have a serial # starting with the letter "C" which is a series of bills that were not printed until 2001. (00:15:14)
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.
MovieFan612