Its a fad right now due to the newness and scaresity of the items. But VCR, CD and DVD all went through their "Fad" time.
Most R/C section did also. In six months wont be this way but will have a mature new scale for the future. Would you run a 1/10 nitro on your desk? No but a 1/64 ~ 1/70 is aok! Hard to fit even a Can car in a pocket but could have a couple of cars pluse controller!
This fills a nitch.
1) Low cost of entering it. Not a huge investment.
2) Simply customizing with user skill or add on kits.
3) Run it just about anywhere.
4) Ready to run.
5) Spure of moment fun.
It evolving with new thinks like games, offroad, tanks, busses and mayin the future construction equipment!
PS: Forgot about the subs!