Yes it does! ; 3
You can see it being done in games like Ninja Gaiden Shadow and TMNT Fall of the Footclan, among many others, and a surprising amount of European-developed GBC games actually use Hblank interrupts on every scanline to change the solid BG colour in order to pull off an Amiga-style gradient in the background, effectively creating a 2nd BG layer! (Though one that only displays vertical gradients, it was also done in a Goemon game by Konami, though to a lesser extent)