That doesn't make sense. I think I've seen one Sport Mode race for it, in 7 months. If I delete my GT-R Pace Car, then what?
It doesn't have to be used in a Sport Mode race. Nor does the dirty R18.
You're not understanding. One has to get the R18 by sheer luck.
All the Missions, Tests, Circuit Experiences, are able to be completed by everyone, to get the pace car. That's not a rare car according to your view.
Again, in circles, we get to choose two pace cars that don't feature in any races other than Custom Race and online Lobby. Why not offer the GT-R? We got the R34 pace cars in the Used car DEALERSHIP, for GT6.
Same for Gr.3 road cars. Depending on color, those are rare as well(if one doesn't follow Famine's cars and colors breakdown). Yet, we can purchase them.