He also mentioned that Maggie wouldn't recognize him.
Use him for light manual labor? There are guns all over, you'd have to have two people watching him at all times to be semi-safe, not exactly endearing him to you.
Third, you would yes. That doesn't meant that everyone would. He could be some punk that would love to go back to his group, which could include family for all we or they know, and bring them this huge prize of a safe haven to take over, supplies, and women to rape. Such a big prize could do great things for him within that group he was a part of. You know you wouldn't do it, but you don't know if Randall would do it, and the farm group didn't know either. All they did know is that it would be a very, very, very serious risk.
Just because the group they ran across in Atlanta turned out to be a bunch of saints, doesn't mean every group will.
In any case, I don't know that there is value going on, we've both stated our sides and I doubt we'll change our minds.