Human energy is still vital to be accounted for.

Plants, vegetables may just grow all by themselves, but someone has to take care of them and oversee the quality and conditions are correct.

A future Van Goth may have a lot of people that would like their artwork. His skill and talent cannot be made cheaper by having free energy.

It really isn't so much about just the free energy, it is also about a give-give society.
Read "And Then There Where None" by Eric Frank Russel.

Although you could have everything for free, it was also very costly.