You have no evidence to back that up, which companies would come onboard if they totally opened up kers?
Dude, green (motor vehicle) technology is a MASSIVE area of development. If a company could come out with a car which uses radically less fuel (petrol/electricity) and costs less to run, this will help boost sales massively. Obviously, your typical sports car buyer isn't likely to be swayed by a "green" car, but people who want to buy a typical family saloon certainly will.
Fuel/petrol is only going to increase with time and as such, green technologies will come into play and become viable. At present, the people who are buying green cars are in the minority, but once fuel the financial incentives for green cars becomes irresistible, there will be a massive shift.
Technologies like KERS will be massive, if it could have a significant effect on the MPG of a car (engine). You could look at adding solar panels to various places on a car (obviously solar panel technology needs to come down in price) and also some drag reduction systems could be developed, so that at high speeds, the car changes shape to reduce drag and fuel consumption
(I saw an advert on the telly today, with exactly this technology).
Fuel saving technologies are going to be HUGE.
The question is would companies want to develop these technologies behind closed doors or by sponsoring sports teams.
Answer: Both. You forget that by having your name pinned to the side of an F1 (or any other sports) car, you are improving brand awareness and you are advertising. I can't think of any other media, with the exception of F1, where cars tour the entire planet. If a company can afford to sponsor an F1 team and also wants global advertising, an F1 car is perfect.
So, if you develop a green technology with an F1 team, you are not only advertising your brand on a global scale, but you are also developing the technology which could be used on road cars, which in turn could improve MPG figures, which in turn will almost certainly improve car/vehicle sales.