See, that DOES make sense to me, but the way everything was phrased (at least to me) didn't portray that train of thought at all. 

If Steven didn't want to help, he could have simply said so and continued on. But he never says that. He NEVER expresses that he doesn't want to help-- in fact, NOW he's walking back to help. Even though he supposedly didn't want to. He instead keeps saying "If you want to help, you can stay. If you don't, you can go"--like that wasn't obvious. He continues to say that even after everyone has expressed interest in helping in spite of the menial task at hand. Like-- just go, dude. Nobody is stopping you. Why are you still here asking that same question? Thus why Abel drew the conclusion that he did.