Maggie Crozat, proprietor of a historic Cajun Country B&B, prefers to let the good times roll. But hard times rock her hostelry when a new cell phone app makes it easy for locals to rent their spare rooms to tourists. With October--and Halloween--approaching, she conjures up a witch-crafty marketing scheme to draw visitors to Pelican, Louisiana. Five local plantation B&Bs host "Pelican's Spooky Past" packages, featuring regional crafts, unique menus,...