Just keep them for yourself, KT. When they are dirty, wipe them over with a damp kitchen roll and use them in cooking recipes or as fried eggs. When you break the shell, you will see whether the egg is still fresh and if it is, use it. Maybe the egg sold to the customer had frozen in the mud, causing the white to be mushy when cooked.
I get quite a few dirty eggs after it rains because the chickens don't wipe their feet before going into the nest box to lay. After wiping the eggs, I keep them in a separate egg box duly marked "For Home Use Only".