To see or not to see

Lee sent me this one. When driving past Lakenheath U.S. Airbase he saw a group of Airmen, probably defaulters, collecting litter from the roadside outside the base. They carried plastic sacks and spiked sticks and wore camouflage fatigues, which is standard wear for the U.S. Forces. What amused Lee was that over the camouflage they wore Day-Glo high-visibility jackets.