Literally who does this?
I've had to before, such as when I had a troubled stomach on the way home from work. I was happier to stuff in a public toilet at a supermarket than walk the rest of the mile with poo dribbling down my trouser legs.
Also, if you're travelling by car, you may be on a journey for some time and suddenly have need. Again, using the public loo at a service station is a better alternative to having to clean a car seat.
