Theres a lot about the materials and construction that may look superficial but have a huge impact (pun intended) on the performance of the pad (density, foam type, construction/gluing techniques) and improve its ability to absorb and transfer energy back to the puck.
Sure the foam absorbs energy but the design itself can dictate how the energy is dissipated, whether into the leg or back into the puck. Id be very skeptical of any claims regarding the skin material improving rebound control.