Decode Slatepack with CyberChef?

I don’t know, but i wonder why someone would not want to encrypt the slatepack in step 1. My view was always that you want to have it encrypted, except for maybe some special cases where it might be preferred to not need encryption from one party, eg. donations via RSR. Do you know of any case where it would make sense to not encrypt SRS step1 slatepack?