The Zazzy Substitution - S4-E3
Sheldon: May I point out that for eight long months, I suffered in silence as your female companion filled our apartment with her off key country music caterwauling, the unappetizing spectacle of grinding a pommel stone against her calloused feet in our living room, and night after night of uninformative TV documentaries about the Jersey Shore.
Leonard: Suffered in silence?
Sheldon: Yes, and I would expect you to do the same.
Leonard: Really? SILENCE!?
Suggested correction: Not being able to afford doesn't necessarily mean he doesn't have the money, especially a man like Sheldon. He works with a budget and he sticks to it. In his budget he has a certain amount set aside for rent, anything more than that and he can't afford it alone.
Nonsense. If he was sticking to a "rigid budget" he wouldn't have even thought of lending a hopeless credit risk like Penny a single cent. Instead he throws a huge bankroll at her without even discussing a repayment plan.
Rubbish, I stick to a strict budget but still have the money to lend to close friends. Like Penny is to him.
He might have different budgets for different things. People could get a higher margin because they could be of more use to the scientific mind of Sheldon.