It would be easier if I could sketch it out, but I'll try.
Imagine a line running vertically through the centre of the photo. Real-world lines parallel to this line will appear to converge on the same point on the horizon as this centreline; the further out (left or right) they start from this centreline, the greater the projected angle of this parallel line to the vertical is. In this case, there are two similar-sized objects a similar distance from the centreline as well as the camera, so their (parallel) shadows will appear as having roughly the same angle to the vertical. And would converge on the same point on the horizon if those shadows were sufficiently long. In other words, this is why you see what you see, and the wide angle lens, which the Zeiss Biogon 60mm is, will exacerbate that effect.
In photos not taken with the sun/light source right in the photographer's back, the effect (still present) gets overwhelmed by the angular projection of the objects with respect to the vertical centreline.