My younger son doesn't have data tariff on his phone. Can't use lightning in a local grocery store.

Since they use my (thus custodial) lnbits instance anyway, they also have a mint available.

my son mints echash at home and spend it at the store without internet access.

how that's not a use case?

(there is an alternative with LNURLw but they don't have a device to scan the QR)