The answer to your question is simple: huge loans that they don't know how to repay...
Before enrolling a flight school, it will show to you, the prospective student, sheets showing 6 digit pilot wages.
What they willingly omit to tell you is that you won't get to the 6 digits before 1 decade after training and that you won't even be able to cover living expenses with your starter salary (without even speaking of a potential need to fund TR).
If you think about it, it's insane.
A 75K program's actual cost rarely exceeds one third of its sales value.
So actually, all these people are genuinely filling the already deep pockets of the FTO's owners....
It's their choice, no one will stop them.