Ye but generally you buy a barn find, just hopefully for a bargain of a price, 2 very different things IMO.
Not always, no. There's been plenty of mentions about finding x car in a barn/field/whatever and no way to trace an owner, and the general response has been "rescue it". Of course the word "rescue" is used because it's a it's a car close to the heart of the enthusiasts discussing it. When it's not a car close to those hearts, it's classed as theft...