Does a motor really need all this circuit to run?
The motor does not need all that circuitry but the lithium ion battery needs all that circuitry to remain safe.

Running the motor directly from the battery is a bad idea. If a lithium ion cell is discharged lower than 2.5 Volts (typical spec) then the next time it is charged, it will get very hot and build up very high internal pressure. There is a high risk of explosion and fire at that point.

If it is charged to a higher voltage than specified, the battery can be damaged or become hazardous.

Lithium ion and lithium polymer batteries are much more dangerous than other rechargeable types. Thus they are always made with embedded electronics to prevent overcharge, overdischarge, and overcurrent conditions. If dangerous conditions are detected, the control IC opens an electronic switch to disconnect the cell from the circuit. 

What you see there are safety circuits plus a charging controller IC. Hope that helps.