[quote=Revans Exile]
From what I know of the book. The Marauder suits had no reason to exist until after the Bug War began.That be like inventing a giant robot to fight Godzilla before Godzilla was even born.
[/quote]

The Marauders in the book were not designed specifically with the Bugs in mind. It seems to imply that they predate the Bug War. In the book, Marauders seemed to be designed to be what body armor and M4's are today: standard infantry attire and armament. Even if they were designed for the Bug War, they still came in very, very early on, early enough that, by the time Rico enlisted, Marauders were being mass-produced and every cap trooper got one. And if their Marauder was destroyed, they got another at no cost to them, so it's not like Marauders were precious resources.