It seems so simple — read about it here.
Businesses that don’t use their parking nights and weekends could allow (read that sell) their parking to others who need it during those times.
I don’t have any data, but I’ll bet Don Shoup does. I would guess, however, that 95% of available parking in central cities is unused during off hours. All that parking could be available for those going to shops, theaters, dinner, or even living in the area. If a person parked under the bank from say 5 PM and was out by 8 AM (most folks who drive cars to work) think of the problems that would be easily solved.
From the mouths of the non parking world.