As to the cat in the porch pictures, there's something wrong with that cat(rabies?). That kind of behavior ain't natural.
Not really. Here in CA they cats prowl the neighborhoods for easy pickens of dogs and cats. We have one up the block that fell through a bedroom window off a fence. He was laying on the fence watching a kid in the bedroom when the fence gave way. The kid luckily had just gone into his mom's room when the cat dropped in. His mom and him stayed there and called the cops. Kitty finally got out of the house and ran down the sidewalk back into the foothills.
DFG here aired a IR video of two cougars hunting like raptors in the Sierra Madre area a few years back. No BS, one cat would walk out front to lure a backyard dog out and the 2nd cat would pounch from behind. And we're talking 100 lb. golden retrievers and other large dogs. The big cat then jumped over the fence with the dog in it's mouth. Awesome display of power in those legs.
DFG did a radio collar study here a few years back and one of the startling things they found out was not that the cats wondered 150 miles out, they found the male territories overlapped considerably. Previously they had thought the cats were very territorial like coyotes but that does not appear to be the case. The other huge suprise was how well the big cats had adapted to urban life and how they lived so close to homes so well. One buddy I know who does depradation for the county here chases cats right among homes, one cat lived in a 100 yard long ditch and was a mile or two from the woods or heavy cover. He get' s many calls of a big cat in someone's back yard sleeping in a tree.
As a good example, recently at a Los Angels Co, fire station I looked down to see a nice cougar print in the concrete. When I asked the firemen if they knew what is was they all thought it was a dog print. This cat had walked right by their firehouse after they had poured the concrete. Kind of puckers you up if you live there and had never seen the cat. I'll see if I can get a pic of the print, my camera had dead batteries that day.