Yes, "impragniert" is German for "waterproof". With a steel toe, I would think they're more likely to be work boots for those engaged in industrial work... all the way up to saw-Mills, Mines, Steel-Works or whatever. Although I didn't actually work in a factory, I still have a pair issued to me around 40 years ago for use when I was venturing into factories. Mine don't have hobnails and were branded "Toe-tectors". Someone could drop a pallet on your foot or drive a fork-lift truck over it without crippling you.
Edit: just looked at your pics more closely. Do you mean that the toe itself has a steel-reinforced cap under the leather (that's what mine have), or are you referring to what looks like a "fender" around the edge of the sole at the toe end?
