The old apple tree in my lawn is dropping apples, so i hurry out there and pick them up before the deer discover them. Sometimes, a squirrel scurries away, so i throw his partially-eaten apple into the woods. I really do not want the deer browsing in my flowerbeds. What they don't know (i.e., that apples grow here) won't hurt them.
Sometimes, what we don't know does eventually hurt us.Ignorance is not always bliss. Ignorance is what keeps the wheel of samsara turning. Through meditation and mindfulness, we begin to see things as they really are.
Really, i should say that what the deer don't know won't hurt me, my feelings, or my garden.