Could be an original fitment.
That front blade is quite stout - thick.
See that the front blade is taller than the peep blade? I would think that they are set up for the same distance and the peep is a shorter blade because it's base is mounted a little higher up in relation to the bore.
Would be perfect for that shot when a quick flip of the thumb brings the peep into position. A neat idea none the less.

I got out to shoot my TypeA 30'06 last weekend.
Can't think of a more perfectly suited light/medium than the 30'06 in a classic Mauser!