This circuit has a relatively high gain, as is expected when you want to amplify a 2-5mV signal to 1V or more. High gain means high sensitivity, and we want to make sure that no specks of dust or any other sudden cartridge signals won't create a large THUMP!

That's what the green resistors called "Input Protection" are there to prevent.

For more in-depth information, Analog Devices has a PDF that describes the whats and the hows of input overvoltage protection.