I love Anna's writing and this blog post! 

For many years I worked as a groom for a barn that followed the circuit tightly, many venues were lacking decent restroom facilities -- luckily we had a motor home with a wonderfully clean washroom which was heaven! I will admit to using a horse trailer and stall as a convenient restroom in a pinch though. 

I remember when I was younger at a particularly large show, where we used a "buddy system". One person using the stall facility and one posted outside the stall door to keep people passing by from peeking in!