I tend to agree that some of the mark-up is due to licensing fees, but part of it is also trying to maximize profit margins. When DAMtoys and Soldier Story can put out a fully loaded figure for around $130, that means the licensing appears to take in about $40-$50 on average for a Sideshow GI Joe. When you look at it from that point of view, you really can question SSC's pricing. I'm paying for a name.
Here's an idea SSC: why not do what some companies do, and provide something that COULD be GI Joe, without naming it GI Joe. You could knock off the licensing fee, charge the consumer a lot less, and have a lot of happy repeat customers! Generic troopers in green uniforms with different sculpts, for example...