I'm not sure how it is now, but many of the older magazines never really made huge money, the value was in the ability to pimp associated products that the magazine had a piece of, like supplements, etc.... For instance, York Barbell, who owned Strength & Health and the original Muscular Development ran them for very little money or operated at a loss. But it was the ability to hawk barbells and supplements in them that kept them around.
Peary Rader's Ironman was always on the edge for a lot of years, but Rader was a decent man with a lot of irons in the fire, so he was able to keep it going.
Muscle Media was EAS's propaganda wing.
I always heard the Weider magazines did the best out of bunch.