Parking on the grass, in fire lanes and/or straight up inventing your own parking space is a HUGE pet peeve for me. I'd have marched right out there and confronted her.
My DH spends an enormous amount of time keeping the driveways and lawns in pristine condition (he used to be in golf course management
) and he would be livid if a daycare parent parked like that.
I'm sorry this happened. Hopefully, she is more aware of where she's parking the next time around.