By having this system in place, on most galaxy sizes, empires will undergo an initial period of rapid expansion, but will reach a soft impediment, as further expansion causes their approval to plummet, and causes them to struggle with some new maluses that situation introduces. The primary purpose of approval is to curb a player's expansion - without this, the rate at which empires could spread across the galaxy would be limited only by their ability to churn out colony-and-supply ships, and all of the empty space in the galaxy would be filled quite rapidly.
