User blog comment:Staw-Hat Luffy/About Kaido/@comment-1707697-20130201182319/@comment-1707697-20130201194829

I assume he needs the Smiles to keep his crew strong, and make it stronger. As powerful as he is, I don't think Kaido can keep the position of Yonko without a crew. And even if he can, I assume Kaido isn't stupid enough not to have a crew to back him up, just in case. Either that, or he really does like power.