I have never seen a discount for Old Lahaina, but they did give Rick a T-shirt that he wears quite a bit.
Old Lahaina Luau doesn't have to work with the timeshare developers, because they seem to pack the show every night. We tried Royal Lahaina Luau with a discount for a timeshare presentation, and the food was blah, but the show was good. The alcohol was good too. But the grounds were not anything like Old Lahaina. Old Lahaina gives each guest a fresh flower lei, and most of the others give cheap shell bead leis, like those free ones you get at Hilo Hattie, every time you walk in the door.