Being called a nit isn’t about pool. It’s about gambling.
Anyone who is wants to stop before the other person, is unwilling to bet as high as the other person, is unwilling to play the other person, and/or refuses to be a through ticket is fair game to be called a nit.
It’s okay to know your boundaries, be clear and consistent about them, and let a bigger gambler call you a nit. One popular nit adage for this situation is, “You need to win it back the same way you lost it.”
Then again, I don’t gamble for the money. I gamble for the competition. So I’m usually open to letting them try to bite back their losses (at the end). My limiting factor is usually time.