I have a boy who will be 3 in about 6 weeks....for the last month or so...he has been taking poop out of his pull-up & smearing it everywhere...his room...the living room...pushing his toy trucks thru it....
Some days he actually uses the potty...& then goes & dumps it in the real toilet. I can figure out how he goes from one extreme to the other.
I dont think he is autistic like most of the poop smearing kids are...so what else could be causing this?
Maybe he needs to be watched more closely and not be given the opportunity to smear until you are convinced he knows that poop goes in the potty. And since he is by your description a "non-autistic poop smearer", you should be able to communicate with him in an effective manner and stop the behavior.