Thanks. Thats an interesting perspective. How do distinguish between a guy volunteering vs me finding a guy willing to come and work with me? Is the latter what you call an internship while the former is volunteering?
If he's doing work for you, and you still accept you may not get what you want at no lasting repercussions to him, it does degenerate to how you feel about it and present it. It really only gets into the nailed down semantics in my model when you're producing something for someone else. He volunteers to do work, you sink the risk of letting him, knowing you may still be on the hook for delivery if it goes bad. If things work out well, good business. If they don't you took a gamble, and got bit.
In your case it really comes down to intent. If you're out for free labor, no bueno. If you're out for helping him and maybe getting something you can work with at the end of it? Bueno.
I just know that even if it started with the understanding you wouldn't pay them, I'd still put aside something for them in the end, especially if the Quality is good.