Is ignorance really bliss?

This, sadly, is a true story which I share with you on this hallowed day - the day when it's your last chance to post first class letters if you want them to get there before Christmas.

My boyfriend went into a shop to buy some stamps for our Christmas cards. At the counter he asked: "May I have a dozen first class stamps, please?"
The cashier replied: "Sorry, they only come in packs of twelve."