If they saved the wrappers, then it's clear they intended to pay for it. No shoplifters ever keep the packaging, they throw it away. Often in the bathrooms, especially the women. As a manager this should have been obvious to them. I know this and I'm not a manager or security guard. There's no reason to press charges when they apologized and offered to pay. It might be company policy, but I can guarantee that they violate company policy all the time. Everyone does, even the most anal policy following employees will violate it.
All they should have done is told them to be more careful and maybe to pay first. Then let them go.
Posted using my HTC Evo