I think you need to ask why a non trivial amount of people would lie about needing to go to the bathroom. This is not a common behavior of teenagers at home, in a museum, at camp, on a canoe trip, or just about anywhere else I can think of...

> just to be disruptive and/or to get out of class

Stopping making a big deal out of it will remove the disruption factor. If you can just get up and leave and nobody pays attention the act will quickly lose its effect.

> to get out of class

This suggests there's a bigger problem there if people are so desperate to get out as to fake a bathroom break, but anyway, why not let them? What's the harm? If these people are bored/disgruntled/etc then you already lost the game and no amount of force or coercion will change their mind.

Teachers can deal with it. It's worth it to have to deal with the second order effects of folks lying to be disruptive or getting out of class so that we don't deny basic bathroom rights to those who need it most.

I have literally ZERO sympathy for any teacher who has shitty (haha) bathroom policies.

Streets are one of the only places that all bank robbers go after a robbery, just to get out of the bank.

This is why we can't have streets... ?!?

Jokes aside, you just provided a very good example of the prison mindset:

Instead of trying to understand the "problem" of students going too often to the bathroom, the default choice is to make the behavior prohibited.