This was done previously.
The owner on paper had to take delivery and also pay registration at time of booking.
The owner would receive a registered car. Take it home and sell it. Invoice + premium + registration.
People always have a solution before hand.
Later cars started being booked / fraudulently as open invoice.
Their are alot of adds on pakwheels selling fresh cars as open invoice cars.
Showroom (company outlets franchises) probably have a leverage from factory to buy xyz cars for display purposes or investment so protect franchise investments (a single Honda/ Toyota dealership costs around 5 crore)
Own premium would never end, and would exist their are situations where dealers actually offer you a discounted price on bookings aswell.
Their might be premium on ready delivery and the same dealer would offer you benefits on booking car from them
Smallest benefits might include free servicing, free Matt's, top cover or else a cash refund.