You have to (sadly) monetise it mate. And tbh it's not such a bad approach as life is gonna be a long stretch of just that for her ie paid for labour.
We've also got ours (13) running eBay and vinted accounts to shift on the stuff we don't want. She gets to keep 100% of her own stuff income and 40% of anything that's 'ours' . She does the parcel packing and trips to PO (which also give us the chance to get her to grab other bits from the local shops

)
Also getting her to design some bits for work (she loves a bit of art, photography and digital design) ...all paid work of course. (Mates rates

)