simple solution then. no unaccomanied minors. end of. yes sometimes it's not as simple as that but it's probably the only way you can prevent this idiocy from continuing.
i believe some airlines already have this policy in place.
Children travelling alone
We do not accept any unaccompanied children under the age of 14 for travel. Children under 14 years of age cannot travel unless accompanied by a person aged 16 years or older who will take responsibility for them. easyJet does not operate an indemnity policy and therefore, under no circumstance, under the Child Protection Act, must another passenger be asked to accept responsibility during flight of an unaccompanied minor.