The same argument about wasting energy can be made from the other perspective. You’re wasting a lot of kinetic/potential energy during the drive that could have been turned into free electricity if the battery had only been preconditioned before departing using utility power. The amount of energy it consumes to precondition is around 2-3 kWh in a 50F garage, which I think could be equal, or less perhaps, when compared to the amount of regenerative braking energy harvested after a relatively short distance.
By not spending the energy before departing, you are preventing the car from being as efficient as it could be, which I think could be more of a waste of energy.
Depends on several factors
If you are leaving the house at 5:01am, and your super off peak rates end at 5am, warming the battery from 4:30am to 5am probably results in it being more cost effective overall, to warm the battery.
But if you are leaving the house at say, 9am, and the highest winter rates are in effect from say, 5:01am through 8:59am? Might be more cost effective to not precondition the battery...