Like many websites, that one is a bit disorganized and slanted toward the amusing.
Diego Garcia is a long, narrow, meandering atoll. It was first developed as a coconut plantation. Now, it is used as a navy port and a launch pad for long-range bombers in the region.
A tour of the island will show you old cemeteries near the old plantation, wild donkies roaming near various antennae, Harvey the Hammerhead in the lagoon and sting rays in the shallows of the ocean side, asian types riding bicycles to work, the airport, the navy docks, and a bunch of WWII-looking buildings that are the housing, clubs and shops.
It's quite interesting for a short stay, but doesn't offer many amenities like fresh food and fresh beer. I wouldn't expect the lineup pictured in the bar either.
Is that strange? It's actually somewhat typical of a militarized atoll IMHO.