Agreed with the "waste" argument. I won't defend the huge power consumption but the energy spent is strictly useful in a utilitarian sense - every joule spent makes it that much harder to perform a 51% attack. Ideally, the energy used to secure the network is widely/evenly distributed among nodes for maximum security benefit (though not usually how it plays out).

However, to say it's all a waste is just an emotional argument because you don't like it. That's fine but it's opinion, not objective fact.