Buying ones own toilet paper has always been a sign of maturity. It's not so much the money factor but more the advance planning - making sure you have it when you need.
Toilet-role stashed away for Inevitable is a sign of Maturity
I have learned the toilet-paper-principal early on my life journey. Never go on a road-trip, hike up a mountain or go anywhere. without have a role stashed away. Toothpaste you can buy on the way(just don't kiss anyone). With soap you can squeezes all the little soap-nuggets together or as a last resort you can use dry-clean (deodorant spray).
If you haven't got toilet-paper you cannot use it.
What is your Toilet paper principal today
What is the one thing you cannot go with out today?
What is your inevitable(must do) - What is your important(toothpaste)-What is your convenient(soap)