Brushing one of our cats today, I noticed something that seems odd. On the front legs and the lower part of their hind legs, the fur on top (front) grows down towards the feet while on the back, to grows the opposite way, up.
Whoever designed cats must have had a reason for this. What is is? 
That’s the direction the fur gets pushed when they groom their faces.
Instead of it being uncomfortably pushed in the wrong direction every time they wash, it just grows that way.
Nope.
Cats do things for their own inscrutable reasons. And they’re weird.
On a similar note, look at the back of a cat’s hind legs. All the cats I’ve ever had have a bald spot on the back of the heel. Remember that cats are toe-walkers, so the heel is the joint that’s halfway up a cat’s hind leg. I don’t know if the fur just gets rubbed off when they sit, or if they never have fur there in the first place. I suppose that I could check this out next time I get a chance to hold a kitten that’s not walking yet, but generally when I do get hold of such a young kitten, my brain melts and all I can do is squee and coo and pet the kitten.