A little old lady went to the grocery store & put the most expensive cat food in her basket. She then went to the check out counter where she told the check out girl, "Nothing but the best for my little kitten on Christmas."
The girl at the cash register said, "I'm sorry, but we can't sell you cat food without proof that you have a cat. A lot of old people buy cat food to eat, & the management wants proof that you are buying the cat food for your cat."
The little old lady went home, picked up her cat & brought it back to the store. They sold her the cat food.
The next day, the old lady went to the store & bought 12 of the most expensive dog cookies - one for each day of Christmas. The cashier this time demanded proof that she now had a dog, claiming that old people sometimes eat dog food.
Frustrated, she went home, came back & brought in her dog. She was then given the dog cookies.
The next day, she brought in a box with a hole in the lid. The little old lady asked the cashier to stick her finger in the hole. The cashier said, "No - you might have a snake in there." The little old lady assured her that there was nothing in the box that would bite her.
So, the cashier put her finger into the box & pulled it out & told the little old lady, "That smells like crap." The little old lady grinned from ear to ear, "Now, my dear, can I please buy 3 rolls of toilet paper?"