That's very common on many stockman patterns, from many makers over many, many years. Seems to be somewhat inherent to the design of the pattern. I've heard, though I've no idea whether it's true, this 'high' placement of the sheepsfoot blade is purposely done to allow easy pinching of the blade with gloved hands.
Most high sheepsfoot blades can be lowered pretty easily, by filing down the kick on the blade, so it'll sit a little lower when closed. The 'kick' is the projection on the lower portion of the tang, which ordinarily rests against the inside of the backspring when closed. Often, very little metal taken off the kick can make a significant difference in the height. Just have to watch out that the nail nick won't be obscured behind adjacent blades, after the sheepsfoot is lowered, and also that the blade edge won't be so low as to collide with the inside of the backspring. There's usually LOTS of free space under the sheepsfoot, so this usually won't be an issue anyway.
David