You are of course correct.. but but but....For people who think morality is objective they will often search for absolutes, black and white boxes where they can neatly sort everything in their lives to keep their worldview intact and orderly. Life is messy, not knowing something with certainty is reality, striving to understand and uncover more as you seek to narrow down possibilities is the essence of open minded scientific inquiry.
Reading the bible is so much easier... requires less effort.. And instead of having to expend effort to seek and search for the knowledge, it is usually forced into most from the day of their birth. The bible comes with social events, games, food and candy.
Earning scientific knowledge through hard work and study is lonely.. social events are extremely rare, and there is no food or candy.