are parents enslaved to yeshiva?

[henche]

1. Yeshivas don't offer pensions to their teachers the way public schools do, so that cost isn't there.
2. The $1000 or so NY spends on student support services is given to private schools as well, another cost not borne by the yeshiva.

Therefore the number you should be comparing with is $8700, the cost of instruction in NY.

1. Pension is part of compensation.  That means we're spending less by paying teachers less. 

2. If you say so, but the difference is 11,300, so that brings it down to 10,300.

[chevron]

In Florida every child that comes from a low income home, the school gets 6000$ per year. And the school in question is not just taking 6000, they require parents to pay more.

See first posts of the cycle, yes the school is giving tuition breaks to parents that work there, but they also pay very low so it's kind of a balance.