When I first started working at school, I had no idea we were supposed to change our shoes before coming in the building. While everyone was sporting their sneakers/flipflops/toilet sandals, I was stuck shuffling around in those awful "visitor's slippers" while trying to make a good impression.
I eventually started bringing two pairs of shoes (of course matching with whatever I was wearing), but the problem was that when I was going home, I'd put them on top of my car while putting my bags inside and then I'd forget they were up there and drive away. Usually I'd get half-way home before I'd notice kids on the street pointing, oncoming drivers with big grins, or the car behind me flashing it's lights, and then I'd realize my nice matching shoes were still on top, or scattered all over the road.
My worst experience with school shoes was the day they rode along on the top of the car until I drove over the bumpy train track crossing, causing them to fall off right in the middle of the tracks! I heard two thumps, realized I forgot my shoes again, and pulled over to the side of the road just as the bell signaling oncoming train started ringing. Fortunately, the train was stopped at the station, giving me time to retrieve the poor shoes.
Overall, I've lost (cuz I didn't hear them fall off) 1 pair of black dress shoes, 2 pairs of Adidas (arrghh!!), and 1 pair of flipflops. Now I just come to school a little late in the mornings and wear the same shoes inside as I do outside. It's easier that way.