If you see God as a "vindictive daddy is the sky", who scares believers into helping someone with their roof, then I understand why you are not a Christian. However, that view shows a remarkable lack of insight into the Christian perspective.
While incarceration only occurs for some bad acts, it's nevertheless a good example. Is the reason that you don't beat little children, a fear of incarceration? I would think not. Even so, Christians are not generally motivated by a fear of hell. They do good for goodness sake.
If I didn't believe in God, yes I would still have a moral compass. I would believe in helping others and doing good generally. I would not want to hurt people. But Christianity adds to that compass. For example, I don't think I would refrain from premarital adult consensual sex, unless I believed it would hurt me or her. But my Christianity teaches me that premarital sex violates God's moral code. It teaches than sex is sacred and belongs in marriage. It teaches that it always causes spiritual harm. I wouldn't necessarily have those insights without Christianity (or another faith that teaches the same thing). I could provide other examples as well.