Part of living in a free society is that you get to have things that aren't required. IF I want to buy the biggest gas guzzling truck there is, I should have the right to do so since I'll be spending my $80k+ of money on it.
Your silly little metaphor would make sense if it was actually about how it "affected others". It's clearly not for the reasons I explained above.
Creating excuses for totalitarianism is fun.
The freedom to impose on other people's freedom is a funny one.
First of all, taking your kids by car to a much better school. Because we sure as hell cannot afford to own property close to those better schools.
Oh, and the best schools are really in the downtown area. Which is why children, kids, teenagers use the public transport from all around the metro area by themselves to get to the schools.
And since you comment further below about winter - yes, of course the kids move around like this in the winter too.
Also, some European countries do a really high effort to make their public schools so good that rich people study in the public centres.
Not kids from age 3-10, and from then on really just a simple one bus or tram route. There's no point pretending this isn't a big issue. You might say it's worth those people leaving the city to make it happen, but saying it's not life-changing for them is doing them a massive disservice.
Try to put your 10-year old kid on public transport half-away across the city in any big European city, especially after the sun is out in the winter.