Hello fellow Tennessean, Jeannie! I'm not sure how your friend was able to convert the meals to snacks.  There is only one official exchange that can be made on any of the Disney Dining Plans. The only 'trading" that is allowed is that Guests may redeem one Table-service entitlement for one Quick-service meal.  The opposite is NOT true.  Using a Table-service credit for a Quick-service meal is not the best financial choice because the Table-service credits are worth more, but it is a good option for those not wanting to be tied down to Advance Dining Reservations everyday.  You can make this exchange as many times as necessary to fit your needs. Entitlements are not supposed to convert any other way.  Happy planning and have a Magical vacation!