That seems like quite the assumption: correlating a user's willingness and ability to subscribe to EN World with how often they play D&D and what role at the table they prefer.
Huh?
It's a pretty well established fact, actually. Over the years there have been literally hundreds of polls addressing various aspects of people's depth of involvement in the hobby as it correlates to their involvement in these forums. It's fairly common to find that the most active participants in the forums are more often than not DM's.
And even if this wasn't backed up by years of polls returning similar results over and over, it's simply logical to assume that DM's tend to be the most active and involved in the hobby and forums like this that help them become better DM's.
The simple fact of the matter is that DM's get more out of sites like this than players do. That's not to say there is no value for a player, but to say that there is more value for a DM.
Is there some reason you wish to take offence to this statement?