One of the problems with entering into Formula One is the sky high costs of building a car. There aren't many organizations out there who can afford to build an F1 car and there are even fewer who can afford to build a good one.
If the FIA decides to allow customer cars in F1 teams like Ferrari, who have expressed interest in this, would be able to sell complete cars to smaller teams wanting to compete. If the rules stayed as the are, however, this would mean Ferrari would have a much easier time winning the constructor's championship, which is where the real money is.
If the rules did change in order to keep constructors like Ferrari from dominating the sport by flooding the track with their own cars, we think this could really benefit the sport. If smaller teams could get started with a cheap(er) car we could see more competition for the driver's championship, and perhaps a return of the "gentleman racer."