The thing is that the ETS races in particular now rivaling the World Champs in terms of importance. All the top drivers are there and very often are running prototype parts on the car.
If you're at the race, then you've got plenty of opportunities to look at the cars, chat with the drivers and mechanics and they can explain what is special about the car and why they are running those parts.
Unfortunately, you would lose that element with just a photograph. It then in turn gives people unrealistic expectations of what teams may be working on, and why, and whether or not the general public can buy the parts. The teams want to make sure parts are perfected before being released - it's probably fair that well over half the stuff that is tested at these big races is ruled out and then never used again.
Let the teams and drivers get on with their job - developing the cars to be the best they can. When they're ready, then I'm sure you can see plenty of pictures of them!