But I did touch on that in the last paragraph -- the energy required on a rocket to get into LEO is $20/kg, or $2k/person. It's a tiny amount of the total cost of launch.
A large crane is far more efficient at lifting items.
But even if you accept you have to use a rocket, the cost of the fuel is trivial compared with the cost of launch.
If you could vary the exhaust velocity of a rocket continuously, so it was equal to the total delta-V so far, the efficiency of converting jet kinetic energy to vehicle energy would be 100%, as the jet would be left stationary in the reference frame of the launcher. (This ignores gravitational potential energy and also that the mass ratio would diverge to infinity at zero velocity, but never mind that.) In practice, using a lower Isp first stage and a higher Isp upper stage partially implements this, and the overall efficiency isn't too bad.