They can; I have occasionally sat down for antipasti at one PM, and gotten up late in the afternoon after many more courses. But meals of this sort are the exception, not the norm, and much of the time is usually spent chatting rather than eating. They also mark special occasions, ranging from weddings and communions through the visits of friends or even Sunday Dinner.
Regular meals tend to be much quicker, a small dish of pasta or a bowl of soup, followed by an entrée (about a quarter pound, 110 g, of fish or meat) with a side dish and a salad. Dessert? At a festive meal it will be a cake or pudding, but day in and day out people generally enjoy a piece of fresh fruit.
The Organization of an Italian Meal

