That is the question people should be asking if you don't like the question "how much extra would you pay not to see ads in you car?" we can do the equivalent "how much of a discount would trade to see ads in your car?"
Everyone will know that and hence car manufacturers and car dealers seriously subsidied by an ad publishers will charge hefty price tag for anyone trying to escape ad prison system.
The web and TV are open enough that you can work around those negative experiences (with ad-blockers on the web or a DVR to skip the ads on TV).
I don't see car manufacturers that engage with this scheme allowing third-party software or hardware that would block the ads. If anything, you'll only see an extra fee to drop the ad.
Well, we were going to sell at $10 without ads, but NOW we sell at $15 without ads, and get $10 with ads.