In his book Led by the Carpenter, D. James Kennedy writes:

A man walked into a little mom-and-pop grocery store and asked, "Do you sell salt?"

"Ha!" said Pop the proprietor. "Do we sell salt! Just look!" And Pop showed the customer one entire wall of shelves stocked with nothing but salt—: Morton salt, iodized salt, kosher salt, sea salt, rock salt, garlic salt, seasoning salt, Epsom salts—every kind of salt imaginable.

"Wow!" said the customer.

"You think that's something?" said Pop with a wave of his hand. "That's nothing! Come look." And Pop led the customer to a back room filled with shelves and bins and cartons and barrels and boxes of salt. "Do we sell salt!" he said.

"Unbelievable!" said the customer.

"You think that's something?" said Pop. "Come! I'll show you salt!" And Pop led the customer down some steps into a huge basement, five times as large as the previous room, filled wall, floor, to ceiling, with every imaginable form and size and shape of salt—, even huge ten-pound salt licks for the cow pasture.

"Incredible!" said the customer. "You really do sell salt!"

"No!" said Pop. "That's just the problem! We never sell salt! But that salt salesman – —Hoo-boy! Does he sell salt!"

Salt that stays on the shelf doesn't do any good at all.