I think we need to remember that school in Europe is usually very very different to school in the US!!
In Switzerland, kids don't even usually go to Kindergarten until 5, they get plenty of developmental time at home. School hours are relatively short: our KG kids begin with only 2 hrs/day for 4-5 sessions/week. All kids return home for lunch for 1-2 hours. School hours are not regulated, they can be 7.30-12 and 1.30-5 but usually aren't anything like that long; my primary school kids had two out of five afternoons each week free, and hours more like 7.30-11.30 and 1.45-3.30 until they were 12/13, even into secondary school. It still isn't usual to push kids into lots of extra-curricular activities, they have art, music and sports at school (many US schools don't) so may have an instrument lesson once a week or be in a gym or sports club once a week, life is a lot more easy-going and less pressured. School is important for social development.
Sadly, the American way has arrived and is having a negative effect, soon our system could become as bad as theirs.
Our kids are expected to walk to school from KG, on their own, with their classmates, not to be fussed over and ferried by adults. They learn from these experiences and are independent. At school they also learn to be punctual and polite and have lots of interesting activities going on, as our system is well influenced by the Steiner philosophies. Often we have mixed grade classes, which works very well for most kids, the hierarchy is a reflection of real life. Our schools are not so huge, either - I know of primary schools (grades 1-6) with 20 or 150 kids and the secondary school my daughters attended was about 150 kids. Schools are local and not miles away. Most classes are around 20 kids, more than 28 per class is not allowed.
I think our 15 year old high-school leavers are a good deal more mature than any Anglophone kids I know. A few go on to a 4 yr programme for university entrance (in 13 subjects), while most will take up a vocational apprenticeship, usually 3-4 years, attending school 1-2 times/week, and earning a small amount while they train. They wouldn't dream of expecting the parents to pay pay pay and while many of your 18 year olds are usually just keen to go and party for 4 years at uni after which they still won't actually be able to DO anything (employability), ours will have a full vocational qualification, often their own apartment and partner and be living a proper adult life - surely this is our aim as parents, to produce responsible adults?!