Well... look at it this way. Since the marks are account bound rather than character bound. When you get the marks and purchase new equipment, most likely, you'll be doing some sort of activity to level up your new gear, correct? Well, you'll be obtaining more marks doing what you needed to do to level up your gear... i.e. obtaining marks leveling up gear that was purchased with said marks. It's a nice way to keep a good flow on your "in game currency." Hope that helps. Happy hunting guardian. :)