Little levity here... This reminds me of ME 
Age 22, young mom, TIIIGHT budget (not a lot of extra cash)
$50/week to feed the 3 of us and diaper the baby
Yup, I'd scrimp on the groceries every week to afford a monthly mommy night out!

But seriously, I actually kinda get what the OP is saying, without infering to her personal life which we know nothing about. I myself wouldn't be thrilled to have my dd blow her lunch money on a powder-puff ticket. But I am all about natural consequences. How many days of lunch would $5 cover? Lets say 2. Fine, you have your powder puff ticket, and for 2 days you can pack a lunch from home. Then we're square.
Similary I have 3 kids. I give them the same lunch money on their accounts. ($20/month) The sooner one kid blows through that, the more sack lunches they pack until the other 2 catch up. So it's about choices... Some mornings they may be too lazy in the morning to make lunch, some days the lunch is "really good" and they want to buy. That's okay, but if there is more month at the end of the money... well they know what to do.
It's not punishment... it's life lessons


