Default [Q] Why does getSystemAvailableFeatures() returns non-existent features on KF ROMs?

Hi there,
A discussion in another thread got me thinking about the Kindle Fire's lack of features (gps, bluetooth, light sensor etc.) compared to other devices so I ran an app called Show Device Features, which basically returns the strings of the features returned by getSystemAvailableFeatures(). I noticed that these features that are not present in the KF appear on the ROM I'm currently using:
light sensor
proximity sensor

There are others I'm not sure about (accelerometer, gyroscope).

I didn't want to hijack that other thread so I'm asking here if anyone knows how this list is populated and what effects it has, and has anyone tried to remove these features from PackageManager in a KF ROM.