Why are hard cover books more expensive than the same book as a soft cover?

Because they are more expensive to make, and take up more shelf space. They also tend to be made and sold first, when there is more demand from people who want new things, and there is no paperback yet available for sale.

There’s also more perceived value in a larger more deluxe object. Though many people prefer paperbacks for the smaller size and weight.

Making the book (hard) cover and securing the pages therein is more labor intensive than a simple printed-on-paper cover and glued in pages.

While it’s true that there are higher production costs in making the hard cover, I’m sure nearly all of the large difference in price can be attributed to supply and demand. Hardcovers are released first, so there is a steep premium for “early access.”

All of the above.

Hard cover books are preferable because they are easier to open, keep open, and lie flat.

They also look better on a shelf, and have a book cover. So they are “classier” to display.