You Probably Didn't Know That William Shakespeare Loved To Go Camping...

It was while he was writing one of his famous plays that a shopping list he'd written to remind himself to pop down to Richards Camping Goods where there were discounted tents in the store's winter sale, got included in some notes Bill's secretary was typing up.
Somehow Bill missed it when he was reading his final draft, the proof readers didn't understand it but rather than make fools of themselves by querying the master, they just ignored it and it was published.
Bill as you might imagine, was really surprised when he went to the first night's performance of his new play and there was the Duke of Gloucester raving on about now being the winter of our discontent...