Because your goal is what your children provide to you - deference to you and honor to you. Good parenting is not focused on what your rewards. Hence the entirely appropriate derision of all such parenting. If you are in that lot, so be it.
The question was:
Explain why Eve should have obeyed god with out referencing any sort of moral obligation. Because he's God? Because he created her? Where is the obligation without a moral obligation?
I'm not in it for honor to me--though I've heard many skeptics use this as a reason for refusing to trust Jesus for salvation, by the way.
The goal is for children to live happy, productive lives. One parent may threaten the child with time outs and punishments, and then the child partly lives in fear, obeys to not be punished, and has trouble overcoming sin.
In our parenting, our children wanted to do well, be better people. Very simple, really.
As for Eve, you've emphasized obligation. I'm trying to emphasize love. Eve loves her Father, wants to please Him, realizes if she eats that fruit, she'll displease Him/dishonor Him, but the fruit looks good . . . we who focus on love worry little about obligation and law, believe it or not.
For example, the law says not to commit adultery, but my spouse and I avoid not just physical entanglement outside our marriage, but all kinds if inappropriate intimacy with others.
Or the law says not to kill, but I strive to love my enemies.
The love of God can overcome the temptation to sin--at times--since sin is pervasive, powerful. Eve sinned.