Your idea of an impulsive financial decision is sending an extra $100 to debt repayment, not spending $100 on shoes.
You calculate how much you're allowed to spend on dinner daily, now that you no longer have that $100 to augment the grocery budget. And then you carefully plan meals such that you'll come in under the already-frugal budget.
(If you read my journal you've seen this already, but in light of my financial past it seemed noteworthy.)
CapitalOne Visa $0.00 100%
CapitalOne Mastercard -$100.00 67%
Chase Amazon Visa -$154.47 0%
Discover -$2,455.64 0%
Medical Financial Solutions -$400.00 60%
Private Student Loans -$10,289.00 0%
Subsidized Student Loans -$85,704.32 0%
Emergency Fund >$3,000.00 100%
Buffer $0.00 0%
iMac $0.00 0%