The U.S. Mint will sell you two rolls of nickels for $8.95. Even though two rolls of nickels are really only $4. You can also buy a bag of 500 nickels for $45.95, even though that's only $25 worth of nickels.
Or you can wait until you get one as change, which is free. But the nickel is the poor relation in the American coin hierarchy. Unless your local merchant has run out of dimes or quarters, you can never get more than one nickel back as change. No one ever has a "take a nickel, leave a nickel" tray.