The days when cars required that have been gone for years now, since the '80s IMO. The old 240s/740s would benifit from doing that on occasion (not even every 30K either IMO) but newer cars have not been having the same throttle base problems that the older models once did and don't ever really require it unless there's a problem. If you had a bad flame trap and had excessive oil film buildup that was causing it to stick, then I'd say clean it but otherwise, just ignore it.
We see these newer cars everyday and never attempt to sell a throttle cleaning service to them because it's not necessary and would be considered a "scam" in my book.