Joseph: maybe parents want to remain part of their community but have also the skills to succeed in the secular world.
So the parents can either suck it up because their schools will stay the way they are (probably illegally) or send to other schools and be branded tuna beigels…
…or at least that’s how it works here in Monsey.
ETA: Plus, there are plenty of schools that have excellent Torah studies without stinting (okay, without stinting TOO MUCH) on the secular studies. They just don’t teach in Yiddish, if that’s a problem. It really, REALLY can be done…