It's not that people do not WANT real tracks, but a good virtual track is a lot nicer to drive than most of the existing real tracks.
I've often heard complaining that the starting position and pitstops actually decide the race nowadays. In F1 you hear that a lot, because a lot of the tracks are not really suitable anymore to overtake (especially in these high downforce cars).
I do not NEED a real race track to have fun. Any layout will do fine if it provides me an opportunity to race side by side next to an opponent. Thàt exact moment defines racing fun for me and not what track/car I'm driving.