The animal crossing the road is crossing its habitat; the road is crossing it too.

The road is the intrusion, though the animal is the one described as being in the way. It is moving through the territory it has always used, and a line was drawn across that territory without consultation. Whose crossing counts as normal depends entirely on which of the two you take as the fixed background.

That question, which thing is the background, quietly decides a lot of arguments. The newcomer, the change, the interruption is defined by whoever got to establish the baseline. When you find yourself annoyed by something in your way, it is worth a moment to ask whether you are the road, since from the other side it very often looks that way.