Oh, they just power the LEDs and allow them to turn on/off. They need so many because they need to be able to address each LED individually for the cool lighting effects they do.
As far as "better" or worse than the TK: hmm it varies. I'm really not a fan of the soldering in that picture, but the rest of the build quality is nice (good PCB, great USB jack, I wouldn't expect it to break). They are both good options. As with many mechanical keyboards, there is no clear winner, just tradeoffs.
If you need a numpad, the obvious choice is to get a lightsaver
