Hydrogen is a storage medium. Fossil fuels are used as the energy source to make the rocket propellant.

I can also guarantee you that fossil fuels were used in the production and distribution of the rocket boosters and that the airplane the video was taken from wouldn't be flying if it didn't have any jet fuel in it's tank.

Humans are smart creatures, but we shouldn't kid ourselves into thinking we would be where we are at now if it weren't for a cheap, albeit limited, supply of highly concentrated energy.