I make exceptions when it comes to Bobby Singer. I didn't have to throw in the legs, did I? I was generous. So I held onto his soul a little longer than he'd have liked-- nothing in the contract prevented that. So don't make it like I don't keep my word. I do. But it's not on me if some idiot signs the line without reading and understanding the terms.
And he should've understood that once your soul's marked for Hell, that's it. We're just going to take it when it's available instead of coming to collect at the close of the deal.