Why do we have school teachers enter numbers at car line pickup when robots can do it?

A Real World Problem & An Automated Solution Awaits
Here’s a practical application that can help schools with parent pickup and reduce unpleasant tasks and time burdening school staff. It really doesn’t involve AI in its operational state, but to speed up the development of this prototype I did use some AI to create a free solution.
This would reduce school operational costs and the toil of needing teachers to enter every parent car’s student pick up number manually. It will also eliminate human errors where people have to stand for almost an hour in all sorts of elements, sometimes in heavy rain or uncomfortable heat to do something we already know we have the technology to automate.
Currently, at my children’s school, there is this unpleasant manual and inefficient process where two teachers have to stand out at the line of cars full of waiting parents and manually enter each number the parents display on a printed card into their cell phone. This number is sent to a system that alerts the kids waiting that their parents have arrived so they can go to pick up line.
Why not QR code and QR code readers?
Many small business use bar codes and we’re all familiar with QR codes. These school pickup cards should have both a number and a large QR code for a machine to read them. That will make them at least be “machine ready” when one of the automated solutions is made available.
Ideally, parents would pull up in line themselves to a scanner mounted to the driver’s side where they could show their card or the QR code on their phone and no teachers would have to stand outside entering in hundreds of numbers every day. It pains me to see great teacher talent being wasted in such a way.
I do not know if the system the teachers currently use has an open API that would allow input from something other than their cell phones but if the app they are using on their phone doesn’t, it is still possible to have a machine read a number derived from a QR code or the printed digits and enter these numbers as if they were entered into a keyboard.
For those interested in the PROOF OF CONCEPT, please check out the working code base on my github:
(https://github.com/aaronbelchamber/school-pickup-system)