FYI: Like Buddha contacted Silverstone, I went the other route and asked at the Sachsenring (wouldn't be surprised if hardly anybody outside Germany knows it) if it were possible to get the track licensed and what it would cost. All the ADAC (german automobile-club which runs it) would ask are a few "copies"
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of LFS for them to give away at competitions or lotteries. However, I doubt they could provide any valuable data of the track (didn't ask, because I didn't want to be too much of a hassle), so that's where money (and workload) becomes an issue again.
I guess you could generalise that: Licenses for big tracks that are run in F1 f.e. will be expensive, while not-well-known tracks will be cheap/no charge for the license itself, but obtaining data will be a problem. Plus, for the majority, driving on the Sachsenring will be no different to driving on a fictional track -- they don't know it, will never drive on it and will hardly ever see it on TV
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.
(I'd love to have Sachsenring, of course, as I'm planning on driving there at least once this year :tilt
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.