Why is a BJT considered "current-controlled"?
In the above circuit Vin is controlling the current going to the base, not the voltage drop across the base and emitter of the transistor itself.  

The voltage drop across Vbe will always be around 0.7V for Vin > 0.7; the excess voltage will be dropped across the R1.  

By changing Vin, you are actually controlling the current going to the base based on the equation:

$$I_B = (Vin-0.7V)/R1$$