My theory is that they are being held by a timeshare salesman and he won't let them go until they agree to purchase something.
LOL..Very possible. While we were there (Myrtle Beach) during Thankgiving week, leaving Mammy's Kitchen, a salesman followed us almost to our car trying to pitch a sale.
Here's a link to the Myrtle Beach fish wrap with more info....http://www.myrtlebeachonline.com/mld/myrtlebeachonline/16215138.htm