You go straight to the heart of the matter when you say that you have noticed some discrepancies in the eating habits of different families and people around Italy. The fact is that everyone has different routines: however, there are some patterns and eating habits that we all have in common.
For example, I would say that you have always had antipasto (starter), primo (first, usually pasta-based course), secondo (second, usually meat or fish-based course), contorno (side-dish) and dolce (dessert) with your relatives exactly because you were with them: family lunches and dinners always have to be special. You have to impress your hosts by entertaining them with food. And woe to you if you don’t throw a feast: at the end of the meal you must be completely full! You know, sharing lots of food is our way of making someone feel welcome.