Do we need a future? If we aren't going to stick to higher density fuels like fossil, nuclear or some sort of interesting synthetic then we are going to struggle to get off the planet earth.

There are two very-long-term futures. One where humanity ends up in space, and one where we get the Chicxulub treatment. One of those paths involves us having so much energy that wasting a bit on holidays is irrelevant, and the other raises the question of how much we need to conserve for future generations anyway given that we're going down the nihilistic path.