Finding themselves suddenly teleported into a snowy town just feels like another day back in Snowdin, huh? I think years of pranking are going to have Papyrus just by default assume it was Sans who did it, the first time, so there's some "ARE YOU SURE YOU DIDN'T DO MAGIC?? BECAUSE THAT WAS PRETTY FAMILIAR" to be had.

re: the Gala, probably Papyrus, yep. At least it's free food, right? (Psst tuck in that shirt.)