When they'd take down the Higher Roller?!
EIFS is Exterior Insulation and Finish Systems, which is a mult-layered exterior wall system that consists of an insulation board, a base coast which is painted onto the insulation board and usually reinforced with fiberglass mesh, and lastly a finish coat that is painted to look like a certain type of stone material.
As for why they didn't do anything with the elevator cores/towers it's really as simple as cutting costs.