[pcthrowaway]

Millions of people play in casinos, that doesn't mean the energy they use isn't a waste and overall negative for society.

Bitcoin is like that times 1,000,000 when it comes to energy usage.

The energy and resources expended mining for diamonds is wasteful also.

[patricius]

Value is subjective, so it is by definition wrong to say that something is objectively a waste. It depends on who you ask.