Believe me, visit Reddit for Minneapolis, the most transit-optimist place you can find, and see what they think about their light rail. Full grown adult women won't ride it. Children? That's almost child endangerment by itself.
I have no problem with homeless people getting free transit if they need it. However, the subset of homeless that are consistently riding for free and making nuisances, they may need to be forcibly kept off the train. It doesn't even need to be police action - install physical barriers, requiring cash or pass, and hand out passes to the homeless like candy with revocation for repeated misbehavior.