I don’t see how school is the same scenario at all. In school, you have a natural break every 45 minutes or so, and can choose to do your business then, rather than disrupt class for everyone. Also, kids do need to learn some control, to pick appropriate times when you can. Most importantly, too many kids abuse the freedom to disrupt or skip class: they have no reason to care about a reprimand whereas an adult probably has their income on the line.
Of course, after saying that, I do have to add that my ex is a teacher who does not want kids to ask. She controls the potential for abuse with a token (beanie baby) allowing only two to go at once, and she has the privilege of a private school with higher standards for their kids