I would like to avoid this situation. The Adafruit Motor shield uses a lot of pins, and the library is programmed for the internal timers, and also hard to understand.
The pins used by the library are pin 3, 4, 5, 6, 7, 8, 9 (only for servo), 10 (only for servo), 11 and 12.
Pin 0 and 1 are for the serial port to the computer.
What LCD+keypad are you using ?
There are LCD+keypad shield that use pin 4,5,6,7,8,9 and A0 for buttons.
You can not use both shield.
If you buy a I2C version of that LCD+keypad, your problems are gone.
Perhaps you can drop both shields and buy the new motor shield and a I2C LCD+keypad.
Or.... it is possible to use both your shields
Keep the Adafruit Motor shield and it's library original.
Rewire the LCD+keypad shield to use pin 2, 13, A0...A5.
You can easily read the buttons from A0 (that is the original pin for the buttons), and the Arduino LCD library can select any pin (also analog pins).