The problem is that almost all prisoners eventually get out, and the last thing we want is for them to come out in worse shape than they went in.  Warehousing Hawaii prisoners in privatized mainland prisons far from their families has proven to be a horrible way to rehabilitate them.  In fact, privatized prisons in general have been a disaster and yet the current administration in DC wants to increase the number of them.  

Remember when prisons used to be called "reformatories"?  Guess what, there was a valid penologic reason for calling them that because prisons are actually supposed to reform their inmates, not further dehumanize them.