I'm in the "NO" group. If you do it for one, you've opened the floodgate for everyone, and there is only so much room in your holding tanks.
If they are kids, they can go on the side of the road. Who cares. If they are men, they can stand between cars. Who cares. If they are women, they can squat between cars and a couple ladies could use a couple blankets for a privacy wall. If they have to "go" THAT bad, people WILL do it anywhere.
I have seen on public beaches, several times, where folks will hold up blankets and make a human shelter so someone else can change from their swim suit to street clothes. What's the difference if caught in traffic like that?
Call me selfish, but maybe I am here. In basic training in the army (1982) we were instructed on the use of the Antropine Auto Injector. During combat, everyone is given 3 injectors (today they are called injector pins for the civilian population). They were used in the event of a gas attack. Instructions were to self-inject with the first one after getting your gas mask and clothing on. Something like 10 minutes later, inject the 2nd one, and then another few minutes later, inject the 3rd one.
We were told, under NO circumstances to share one with someone else, if they lost theirs for some reason. All 3 were needed to safeguard our lives. Sharing would guarantee death for you AND them as all 3 were required to save your life.
At that point, I started applying that same principle to my own life. If folks around do not prepare, plan, and make arrangements for an impending event, and I HAVE, don't expect me to care for you! I'm prepared, I'm not a social worker! I've prepared to save my life and take care of my needs, not yours because you didn't think it through and was expecting someone else to take care of you! Sorry Charlie! I have only 3 injectors, and if I share, we both die.