Someone who does not make any money doesn't need to care about student loans either. Please correct me if I'm wrong, but the debt collectors can only collect what exists. They can't force you into the debtors prison. As long as you don't have anything, you don't have to worry about anyone coming after you (in the USA).
If you have assets you need to care about debt but the same is not true of an income share agreement. You can have assets without income from sources other than selling those assets.
