I guess its because Initial D is based pretty much on illegal
street racing. They don't base it on the legal circuit concept, but
pretty much illegal mountain racing.
With Shuichi Shigeno the author having a real life AE101 engine
transplanted into his Hachi Roku, and King Dori Dori Keichii
Tsuchiya ensuring that the anime doesn't go too much out of
realism, its hard not to imagine ID is not the hottest animated
racing manga now. With the catchy Eurobeat themes and flashy sports
cars and characters that pack entrancing identities, ID really is
addictive. SegaRosso adds to that by creating Initial D Arcade
Stage. Even more money flows into their pockets with this
monopolisation.
Maybe I'm wrong, but over the past few years, Mt. Haruna (Akina's
real name) has seen pretty much races and its share of accidents.
This prompted the Jap government to step up measures to prevent
such things from happening again. Includes stuff like placing speed
strips at the 5 Hairpins and shallowing out the drain gutters. So
no drifting and stuff. 
Basically, its like every racer boy's dream. Jap cars and such,
going faster not only on straights, but in the thrill of drifting
across hairpins at crazy speeds.
