Supermarket Humour

You might have heard this saying before, but I haven't; usually I'm on another planet from everyone else.
I went out to stock up on groceries and to breathe some fresh air before I start singing today.
There was a two-for-one offer on bog paper and I asked the checkout guy if you can put toilet rolls in the food bank box.
'Yes', he said.
'No job is complete without the paperwork'.