I've done something similar to this when I was wasted at McDonalds with friends and some hams they'd met in the pub. I was plowing into my food and the heaviest one comes out with "Wow, its not fair that you get to eat all that and still stay thin..."  I deadpanned her and loudly exclaimed "OMG, do you think I eat like this everyday?! Oh shit no. Look at all this, look at all this food! Theres so much! I can't eat like this everyday!?! There's so much of it, I'd end up huge if I ate like this everyday!? WHO COULD EVEN EAT THIS MUCH FOOD EVERYDAY??!?!?" I was drunk and overdramatic, but I continued to eat laughing, laughing at her and the possibility that I could eat all this deep fried shit everyday sober.  "Imagine though?! All these nuggets when you're not wasted?! What would you eat it for, lunch everyday?! Oh my god you'd feel so horrible all the time, and the calories!? Oh my god lets see what the calorie content is ..... HOLY SHIT ITS MORE THAN MY USUAL DINNER EVERYDAY HAHAHAHAHA seriously who would eat this everyday?!?!?" She sat eating the last of her chips hopefully reflecting on her life choices, but who knows. She was a death fat so the guilt probably was washed away by the cooking oil and ketchup.