What possible rationale could there be, for not allowing kids to walk or bike to school if they’re close enough to do so? It’s healthy exercise and it’s not burning fossil fuels.
At issue isn't so much the kids who walk or bike to school but the special snowflakes whose special snowflake parents think they're too important to wait in line at the drop-off/pick-up zones. These Very Important Snowflakes believe that they are entitled to use the visitor parking lot to drop off their kids because their time is just too valuable to waste waiting with the less-special snowflakes.
Unfortunately, everyone is a Very Important Snowflake so now the visitor lot, not designed for so much traffic because parents used to send their kids to school on the bus, has become crowded with lots of moving cars, small children and impatient parents.
It's a tragedy waiting to happen. And when it does, the school is going to get sued and the principal will get fired.
Sadly, the kids who walk or bike to school now have to be driven thanks to the Very Important Snowflakes.