One day, while going to the shop, I passed  by a retirement village.
 
On the front lawn were six old ladies, lying naked on the grass.
I thought this was a bit unusual, but continued on my way.
On my return trip, I passed the same retirement village
with the same six old ladies lying naked on the lawn.
This time my curiosity got the better of me and I  
went inside to talk to the retirement village Administrator, and asked her,
 
"Do you know there are six ladies lying naked on your front  lawn?
 
"Yes," she said, "aren't they darlings?
They're retired prostitutes - they're having a yard sale."