Mb, now that you mention it...
I had not noticed it before either.
We've been driving up and down a local street several times a week for over 13 years, and just recently, my wife says, "Have you ever seen that driveway between the trees?" Next time by, she shows me this narrow gravel driveway that seems to lead to something behind the house facing the street. We don't know what's back there, but whatever it is, they have alot of privacy (a lot of privacy? -real estate pun) in the midst of the urban environs.