
They don't know anything about making soap and crap, beauty products, and are ordinary people doing and know about ordinary things. They're not some smart ass that's getting 150% on every history test while having the free time to google "How to make beauty products and get rich after being reincarnated into another world".
Chapter 24 started out so wholesome and funny...but then that last panel really stuck with me, and I think we don't have to guess what happens next.