They could make this as nearly efficient as a plug-in if they can make the charging plate retractable so that it latches itself to the underneath of the car. It would then automatically unlatch and retract once you power on the car or when fully recharged.
It seems like the current motto is save your upgrade money and save the environment. Incurring another set of tremendous efficiency losses is bad for the electric grid especially when the plug-in vehicles go main stream. We took great pains and upgrades to smart meters in order to reduce losses of 5% from the grid, and with the introduction of wireless, adding losses of 10% or more is unacceptable.