Parking meter are not sold by the best technology, they are sold by the best kickbacks.
I worked for a company, and wrote the software for a street level parking kiosk that could do pay by space (enter a stall number), pay and display (put a ticket on the dash), and pay by plate (enter your plate number) all at the same time, and at the customers choosing. By having a slightly larger unit for every 10-15 spaces, you could offer payment by coin, bill, credit, cell phone, & stored value card (Gift Card).
Often though all the features that made sense (as a client is concerned) were disabled so that the revenue stream from parking and mostly ticketing is increased - Greed.
Of course, there are plenty of stupid meters out there. Most of the technology is still around the Commodore 64 era, and has never been improved. Any improvements you see are mostly cosmetic - ie, "New Fiber Optic Communications" are actually just a Serial to Ethernet converter, hooked into the existing RS-485 port on the machine.