I don't think they're German at all. The men look French or Austrian. In fact, the pictures on that page are something of a lottery.
At first I thought they might be French museum pieces pressed into service, but here's an interesting thing: if you right-click on the photo as if to save it, the caption thingy (for which I'm sure there's a more correct name) reads dummymortars.jpeg
If you save the pic and blow it up, that's what they appear to be; decoys, possibly French.
__________________
"Sometimes things that are not true are included in Wikipedia. While at first glance that may appear like a very great problem for Wikipedia, in reality is it not. In fact, it's a good thing." - Wikipedia.