Most R/C vehicles in the 'toy grade' class (maybe all of them) are like that--all or nothing speed and steering.
It's in a way a regression from the way things were in the 1980's. At least then, there were some RTR vehicles out there that had digital-proportional steering and throttle. There were also a lot of cars that only steered in forward, or didn't have reverse. Some didn't even steer, they went forward in a straight line or turned (in one direction) in reverse.
Nowadays virtually all toy-grade R/C will go forward and reverse and steer in either direction. But only full-speed/off and full left/right/straight (this is commonly called "full-function"). Digital-proportional control however, is near-nonexistent (since the demise of Radio Shack's XMods line) unless you go to hobby-grade build-it-yourself vehicles--in much larger scales. Which in itself is weird since you'd think technological advances over the past almost 40-odd years would have brought the cost of proportional control down far enough to make it feasible in at least some of the low-to-mid range R/C cars out there. Even low-end quadcopters have fairly fine-grained three-channel controls.
I have a Chinese-market R/C transit bus with a gigahertz frequency controller that is paired with the vehicle much like a typical quadcopter. You can make the doors open and close, start the "engine" sounds (necessary to drive it), a back-up beeper in reverse and turn signals when it turns left or right. But you still can't control the speed or degree of left/right steering.
I guess the market just isn't there for anything better.
---PCJ
