It's better that prison inmates are forced labor than simply living off taxpayers.

Hard disagree, and I think it's a false dichotomy. Having a class of people that can be leased out for well under minimum wage hurts the rest of society. And I already said I'm not opposed to prisoners working, it just has to be either at competitive wages (in which case I don't see corporations going out of their way to hire prisoners anyway), or in sectors where the savings benefit the taxpayer.

But simply 'prisoners working' does not, in and of itself, benefit taxpayers, and can in fact negatively impact them.

As I said, the state getting involved in business - which is what prisoners working is - is a very tricky business, and must be handled with utmost care.