And for the record, I had to work less to get to good school back then.
The fact is that they aren't working extra, not for a job anyway. The extra work comes in the time making dried beans instead of buying canned, in repairing stuff poorly, in shopping around for a doctor that takes the state health insurance or an affordable option if you have none at all, in taking busses (if they are available), and other unpaid things. Your child will be lucky to afford the activities that gets them a 'good' education, especially if they have to work.
That is exactly OP's point: for OP, if a child's "working hours" includes university prep and resume-padding sports activities, then an adult's "working hours" includes housework, grocery shopping, dealing with insurance and taxes, and commute/family chauffeur time.