Why is using an opening explorer not considered cheating in daily games?

Recently in a daily game, my opponent told me they were using an openings explorer.

According to the Fair play policy: "You may use Opening Explorer or other books without engine evaluations in Daily chess only (not in Online / Live play)"

Why is that?

Plz let me know in the comments

Perhaps it is there if you want to learn about that opening, you would not have to wait until you have finished the game rather you just learn about the theory. This is just speculation though.

Daily chess is the site's version of correspondence chess where those types of resources are allowed. It's part of what daily is.

Oh I didn't know that thanks

Exact, is chess correspondence and I look for learning more about of it's.

Also, copying some moves from a list won't win you the game if you don't know what you are doing. Eventually you will have to go out of book.