Footprints on the Ground

I was hoping that if I build a house there, these footprints would no longer cross the property. Instead, they would only be found outside. 
That‘s not the case! As you can see in the picture.
I noticed that these footprints always appear in roughly the same place, but in different formations.
I suspect this might be related to the Season Pack. 
When there‘s snow on the ground, you can also see the footprints of the Sims where they walked through. 
I hope this information will help for better understand this phenomenon. 
Thank you for checking.