Have refrained from sharing this before, buuuuuuuut ....

Came to work this morning, and found that someone had set up camp in the portico of the building I work in. No-one in sight, but mega debris left behind. I would like to know, from a purely scientific basis, what possible scenario would include :

• 7-8 empty and semi-empty packets of Dine cat food.
• 1 broken bottle of cheap sherry.
• 3 used syringes (capped).
• a baby soother.
• many many cigarette butts.
• the wrappings from at least 2 soap bars.
• various items of discarded clothing including underwear.
• 3 empty bottles of hair shampoo.
• orange peel.
• 1 cigarette lighter (empty).
• the supports and foam packing from a small pallet.
• a secondhand paperback copy of Pride and Prejudice (much used).
• a couple of packets of jelly babies (broken and contents scattered).
• a whole onion (undamaged).

Can anyone enlighten me? And yes, I had to clean it up. Thank god for cheap woollies tongs.