Sonic Channel staff on their blog:
It is Knuckles being worthy of Power Type, carrying large luggages going on an unfamiliar journey.
It’s this Golden Week season. Knuckles is usually guarding the Master Emerald, but he would probably want to try to travel around somewhere like this once in a while, wouldn’t he?
About the decorations, there seemed to be many people noticing the camera, but the second bag looked a little difficult. Even so, there were also people answering up to traveling with camera, bag, and sunglasses.