Just the newest home cooking fad of the day, I’d say. Which seems odd since they’re certainly not a new cooking innovation-- greasy spoon diners have been using large flat top metal grills for decades. It is an efficient way to cook large amounts of food.
My sis and bro-in-law got one and invited us over for dinner. They made us a Benihana-style feast with Hibachi rice and various veggies and meats. It was delicious! Bro-in-law does need to work on his skills at spatula-flipping shrimp directly into our mouths, making onion volcanoes, and such though.