Yeah, we wrote BITS almost entirely for practical reasons. Several groups at Intel use it to test both the BIOS and the CPU itself. (You have to have enough functionality to boot an OS, but once you have that, BITS can easily test things like CPU power management or MSR configuration.)

The module that displays presentation slides using EFI_GRAPHICS_OUTPUT_PROTOCOL, on the other hand, was definitely "because we could". https://www.youtube.com/watch?v=bYQ_lq5dcvM#t=22m56s