I don't have a huge appetite, and I'm vegetarian, but that doesn't prevent me from dropping top dollars at top-end buffets, especially at top hotels in Asia. I think for me it's more about the sense of bountifulness, the presentation (colors, shapes, arrangement), the extravagance, and the ambiance. I definitely don't get my money's worth in terms of value for the food, but it's entertaining and fun nonetheless.
I have to admit that I do love desserts, and I'd rather go to a dessert buffet. The Tiffin Lounge at the Grand Hyatt Hong Kong used to be my favorite for that, but it hasn't been as good the past few years.