There's your answer. Autox is fun to do, but not fun to watch. Drifting is fun to watch.

The downfall of drifting, in spite of its current popularity, is that the "kids" (teens and 20-somethings) who are so enamored with it won't pony up to pay entry fees to DO it. They're only willing ot pay their $5 entry fee to WATCH it. Grassroots level drifting doesn't appear to be thriving as a result.