I understand it's an odd question but please hear me out.
In our home my cousins take a plate of food for dinner.
They take 2-3 spoonfuls.
Then an hour later they do it again.
It's frustrating, really. They aren't paying for the food, yet they and certain others waste... constantly. We buy $150 in food... $80 or so feeds the garbage can. It doesn't stop at food. They leave many hot lightbulbs on in the basement when no one is in the room. Sometimes throughout the night. And in the main bathroom 16 of the hot lightbulbs are turned on to the brightest setting throughout the night.
Water is left running. Clothes are worn only once, Etc.
Here's the kicker: I'd go down to the basement when everyone went to bed to turn the lights off. I'd then slip into bed. I kid you not three minutes later I hear feet going downstairs. Then, a minute later, they return. I wait a while, go down, and lo and behold they're all on again. It's a vast, cool basement... and it's being lit for the ghosts... argh..
Is waste in its severest and mildest forms a mental disorder?
It's irrational. I get a plate of food I didn't pay for, eat a bite or two, and waste it. Totally sane of me. Might as well take three plates and waste them since it's rational. I'll leave every light on all the time as well.
Either it's rational or irrational.
Madness, I say.
The term: "Waste not, want not" is surprisingly true.