WWE doesn't have a certain image for it's champions. Mick Foley is a 3 time WWE champion and he isn't a muscular guy at all. There are a ton of champions who don't look like they're sculpted out of stone or anything like that. But, it is true that Vince McMahon has a soft spot for the big muscular guys like Batista and HHH.
A man can look like HHH without steroids. You just have to work hard in the gym and eat the correct diet. People are just so easy to point the finger at someone and say, "Oh, that guy is on 'roids". And, in all reality, the guy probably worked his ass off for years and years to get that body.
John Cena was on the Howard Stern show back when that Marine movie came out and Howard's listeners were lambasting him with accusations of steroid use. Cena denied them and even spoke about steroid abuse and how he doesn't do that to his body. He went on to tell Howard Stern that he played football since he was 12 or 13 and has been basically working out and lifting weights SINCE then.
That doesn't mean that Cena isn't REALLY taking steroids. I really don't know and neither do you. But taking steroids in professional wrestling has no bearing on a wrestlers performace IN THE RING. In football, on the other hand, it would have a whole lot of bearing on how the outcome could be.