Very interesting points, and I see your point between all five, although except maybe praepropere? while in theory i can see this helps syncronizing communities, especially people with different lives (such as families), to sit down for the same dinner ritual. But in practice I have friends and family some of whom 1) have very active lifestyles such as running to/from work, and so requires more snacks to keep stable energy levels and 2) they have different eating habits for other reasons such as avoiding the psychological effects of truly feeling hungry. In either way, we keep having shared dinner rituals, they just eat different amounts.

So i dont really see how the is a bad lifestyle or some ethical shortcoming, but just a rule to adhere to a specific social norm.