I've watched several videos on the Hummer, and 99% of them when they work with the off-road capabilities always seem to miss a very important fact when it comes with activating the Front Lockers. You must hold down the Front Locker Switch for 5+ seconds after Rear Virtual Lockers are engaged to engage the Front Locker. It is not a simple toggle switch press.
Of course they do. How many Hummer owners consider the grass next to their driveway as "Off roading"?