I want to clarify that, backlit keyboard is not necessary categorize as a "Gaming Keyboard". It is a functionality that for people like to use their computer with lights off.
It helps when briefing with my colleagues, showing animation work on monitors, with dim lights.
Same true when macro keys, LCD screen, volume roller, headphone jack, mute button on keyboards.
I don't know how much time I can save at the office, with adobe suite, maya, 3dsmax...etc.
And of course, playing dayz ingame night time with room lights off is supa fun