Brain energy
Our brains always optimise for saving energy. For its size, it drains a big chunk of our energy reserves.
So we opt for low-energy pleasures, preferably the ones being pushed at us. It takes energy to move from that low energy to a place where our minds get stretched and expanded.
We know this.
And some days we are too tired to apply that energy.
Those are the days to consciously do what generates more energy.