On a slightly different note (see what I did there), why do people ask if you have anything smaller? Of course you haven't.
I'd like to buy a packet of crisps with a fifty.
Usually people do, but they like to be flash with the cash. Daft if you ask me. Why carry around 500 quid in 50's when you can just use your bank card in 99% of places.
Then again if waving around that much cash makes you happy then it's up to you.