This is what happens when finders cannot keep their mouths shut.
Should they always?
Being serious, is this only in the UK? If...ahem... I.... a person bought an old house and while remodeling, (built in the 1930’s)and found $10,000 in the walls, about $60,000 in stocks and MANY silver, gold and antique coins must I...ahem... someone give them back to the person I... ahem... that person bought the property from? Isn’t it part of the property bought?