The oils on your skin soak into the paper, they cant be wiped off even with a alcohol soaked rag, they are embedded in the paper. You have to soak the paper with alcohol to cause the print to disperse. Unfortunately you cant wear gloves for everything, like collecting postage and tracking. You can mitigate this by wiping your hands down with alcohol before buying them, the biggest cause of oil on your hand is touching your face.
This is why a box of disposable latex gloves are a must if you send drugs to anyone.