This is not a joystick, just interface to arcade sticks of an arcade. I don't have good experience with keyboard hacks. This is a robust chip, and it's very easy to hook up your arcade sticks. just like ipac etc. This one is the cheapest of them all.
The point was more that this is all standardized in USB, so unless your device is very weird, it should 'just work'. There's not really any reason for a hardware vendor to design their own protocol when USB comes with one; then they don't have to write drivers and can leverage example code for the hardware. It's pretty safe to assume that any joystick/gamepad/arcade controller hardware with a USB interface will work with Raspberry Pi (or any other Linux box).
But really all these input devices are basically the same. A number of analog inputs (sticks, wheels, whatever) and a number of digital inputs (buttons). If you can find a board that has the necessary set of inputs from a cheap joystick or something you should be able to hack it into your own controller hardware quite easily. If you want to save a few bucks and like that sort of thing, anyway .