My wife is an elementary school teacher and she lets her students choose whether they want to participate or not each day.

Most kids do it because they are following along with the rest, but some do actually sit out during the pledge

Or you can do it with duck.com for free

So that you can turn it in and off and control the humidity in your space with advanced timers and automations. Maybe someone is using for their plants and wants it run on an as needed basis.

It’s not too hard, but it’s more costly, and consumers want a cheap as possible.