Mix butter with the garlic, pepper, and Italian seasoning.
Heat a gas or charcoal grill and put oysters on the half shell right over the hottest part. Spoon the seasoned butter over the oysters enough so that some of it will overflow into the fire and flame up a bit.
The oysters are ready when they puff up and get curly on the sides. Sprinkle the grated Parmesan and Romano and the parsley on top. Serve on the shells immediately with hot French bread.