Not sure if this is Miami only but so many people I talk to work at the local chabad school and often it boils down to getting a discount for their kids... So in short it's like this flow chart :
School charges a ton - pays crap - parents that work there get discount for kids while being paid crap - school claims that they need to charge a ton and pay crap because low cash flow - conviently ignoring the teacher patent discounts.
So, parents are slaves to the institution, quality teacher without Kids there would work there given the terrible wages, the school has cash flow issues due to this and it pretty much helps foster nepotism and coddles friends.
Reason #250 id never send my kids to a traditional yeshiva operating like this