The numbnut sign is most likely not made by whomever is posting it here, just a pasted clip from Art Station. If the designer made it rights free/public domain/copyleft/whatever, they're technically ok using it. Can't claim originality, though, if they're all copy-catting. And if they looked at someone else's then made their own that's practically identical in Photoshop or whatever, isn't that kinda the very thing they're yowling should not be allowed? It is indeed a puzzlement.