Why do people eat mac and cheese from a box?

On researching my previous question I found countless photos of mac and cheese boxes. I've never had these but I'm guessing you add water and boil or something. My question is why? Any idiot can boil pasta and a basic cheese sauce is virtually foolproof, roux + liquid + cheese + more cheese. Yet there's hundreds of brands of these boxes which suggests people actually but them, but why?
Why do people eat mac and cheese from a box?
I have no shame
The bailiffs took my cooker, I've only got a kettle
I'm stocking up the nuclear bunker
Cheese comes in a tube how you supposed to grate it
I can feed a family of ten for a dollar
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Why do people eat mac and cheese from a box?
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