Why?

Saw the discarded pizza packets in a superstore car park. Apart from being irritated by the total disregard for the environment, I am curious as to why someone left it there.

Was it because someone was so hungry they couldn't wait to get home to cook the pizza and decided to eat it raw?
Maybe they have a car that has an oven and cooked it on the way home - or did they place it, in foil, on their car engine and arrived with the perfect, after shopping, 'take away'
Of course, they could be phantom 'fly tippers' who carry their rubbish to the car park and leave it there.
Oh well - I'll never know.