Why would a perfect, complete God create humanity?

I understand (from a theological standpoint) that that could be in his "divine will" or whatever, but why is that so? God didn't NEED the company; he didn't NEED to create something in his image (because he is perfect and lacking in nothing, by definition), but he toyed around with creation anyway, and for some reason thinks that it's fun to send the bad ones to Hell and the good ones to Heaven as part of his little game. What say you?