In the past I've compared fins to Crescent wrenches, people use Crescent wrenches incorrectly as hammers and pry bars all the time, but if you do this don't complain that it makes terrible hammer. Also, if someone gave you a Crescent wrench, but you never knew the jaws were adjustable, it would a be a useless hunk of metal, other than for the hammer and pry bar uses, so you'd have a tough time understanding why it was made and what it was used for.
Other tools do a better job, open or boxed end wrenches and sockets are better, but there's still a crescent wrench in ever tool box and on every work bench.
