While I do have Nick GAS, I do find this to be pleasant surprise as it was one of my favorite game shows to run on Nickelodeon. However....why? I see two options.
1) Nick GAS is pretty much dead and maybe they want somewhere to air these shows occasionally, although a 'Classics Nick' channel would probably be better for shows ranging from Rugrats to Kenan & Kel to GUTS.
2) They want to revive the show. They tried reviving Wild and Crazy Kids a few years ago, and while I thought it was fine for a revival, it just didn't live up to the original, and it failed miserably. I wouldn't mind it though, I just can't see them putting in the execution like they did the 90s version, I mean, just look at it. Would they really make it look that good and put that much work into it again?