My take on it is that he didn't have to; after all "Elvis" was a household name.
Mind you, I was born after Elvis died so I may very well be talking out of my rear (which isn't new (IMG:style_emoticons/default/tongue.gif
) ); but just about everything that had the Elvis name on it was selling well, just like today (even the sh*tty soundtracks, that sold even better than the studio albums; which is propably why the Colonel kept on the same business model).
I actually like the Colonel. Elvis was the very first world‘s superstar, and there was no precedent in how to manage a superstar; and propably the tv shows wouldn‘t pay Elvis for showing up. Which is why the Colonel turned down Time Magazine ... which I think was pretty cool. As I read it, the magazine called the Colonel up and wanted him to provide a picture of Elvis to put on the cover – for free. The Colonel wouldn‘t hear of such nonsense. So the representative from Time Magazine said "Wait, we are Time Magazine" (or something along those lines) which got him (or her) the reply: "You don‘t understand, we don‘t need you."
The Colonel was just, as the best of his abilities, trying to protect his client‘s interests (at least in most cases). If Larry Geller is to be believed it was pretty shocking that he wanted Elvis on the stage after about an hour (I think it was), despite being almost comatose; however the Colonel severly disliked canceling concerts on the same day they were supposed to happen ...which I understand (it could potentially alienate casual fans and might have a ripple effect).
What I don‘t understand, and will never understand, is one f*ck up that the Colonel did. On a movie set (on either Blue Hawaii or Paradise Hawaiian style, if I remember correctly) he shouted that they should stop filming, because Elvis was using his own watch, and in the business agreement it stated that the movie production firm had to pay Elvis and the Colonel if Elvis was using his own wardrobe. They commenced filming again with a watch from the props department. And they lost out on 25 thousand dollars.