Armstrong Williams scandal

By now you've heard that Williams was a paid shill for the Bush administration. What I can't fathom is why the administration would feel the need to pay off a commentator in the first place! Right-wing radio is filled with hosts who pimp for Bush for free (Hannity, Rush, etc.). Why feel the need to pay off one of them, and for one specific issue?

Which begs a larger point- while Williams certainly should have disclosed his paid spokesman status when appearing on other news shows, is it really wrong to accept payment for promoting something you believe anyway? Why not get an extra paycheck for saying something you were going to anyway? However, as a "conservative", he probably should have turned down the money on principle- you know, waste of taxpayer money, big government, blah, blah, blah.