The problem with that is that it's paid with the loss of freedom (otherwise you have to come up with a separate rehabilitation system for those who are dangerou

The problem with that is that it's paid with the loss of freedom (otherwise you have to come up with a separate rehabilitation system for those who are dangerous and solve the same problem all over again). And the loss of freedom is the main problem of things like debt-fueled servitude, which is considered undesireable in the West.