I can go into most bathrooms and stand under the shower-head and turn it on. Is there some purpose or benefit to taking a shower?
There's no reason to. It's just an interactive object for the sake of having an interactive object.
Like Professor Chaos you hate the world and it is your wish in a similar vein to Chaos's plan that leaving the showers on in every house will eventually bring doom. So yeah no point but it is neat that the state (on/off) persists when you leave.