Are the rewards desirable? That's an interesting discusion.
Historically, it has allowed humanity to switch to better forms of money: https://en.wikipedia.org/wiki/Gresham's_law
If you buy in the present what others want to own in the future, you create value for yourself as the price of the asset rises.
You can also understand Bitcoin as a business. Assuming it's a better form of money, it allows any agent of the system to better store or transfer money.
By owning Bitcoin you are assuming a risk, but also making the total value locked (TVL) bigger, through making the token less volatile. That helps. :-)