Back when I was a kid my mother took me to the doctor whose office was in a shopping center with a large parking lot with quite a slope. I was in the back seat and was about to get out of the driver’s side door when my mother told me to use the other door. I did, and just as I closed the door a car - with the parking brake not set - slammed into the rear driver’s side door.
So I always use my parking brake. I’ve maybe driven with it on twice in 55 years of driving.
In my car, the parking brake is THE way to have the car not move. The automatic transmission has 3 settings: R, N, & D; there is no P. D+parking brake or R+parking brake is how you make the car sit still whether the engine is on or off.
The parking brake control is a large push-button sort of thing on the console. I use at many many traffic lights to keep the car from creeping. The car also has an automatic anti-creep braking mode that’s always active, but particularly on an upslope it’s not quite aggressive enough and the car can roll backwards.
Conveniently, if you do have the parking brake set and apply enough throttle to make it obvious you’re trying to drive off, it auto-releases. So it’s impossible to drive off with the parking brake on.
why does your creep forward when you’re at a traffic light? Don’t you have your foot on the brake? 
Why should I have to do something boring and manual like holding foot pressure on the brake? That’s positively 1970s pre-computerized mechanical nonsense. I commanded the car to stop. That means I want it stay stopped until I want it to go; don’t just start going again on your own.
That’s what the automatic anti-creep feature is meant to take care of. But it’s just a bit too wimpy to be 100% reliable.
I don’t think it applies on your own private property, but in Maine, it is (or was) actually a state law to set the brake when your car is parked on a public way or in a parking lot. I have been out of law enforcement for several years, but it seems unlikely it was repealed. Most people were surprised to learn it was a law, even for automatic equipped cars, even though a functioning parking brake is part of the annual vehicle safety inspection.
Someone above mentioned driving off with the brake still set, every time they set it. If you can’t tell within just a few feet that you are trying to drive with the parking brake on, it likely needs to be adjusted to hold tighter. A car shouldn’t be able to move easily with the brake set.
Well, unless it’s the first time you’ve ever driven, and you have nothing to compare it to.
The first time I ever drove, my dad forgot to tell me to take the parking brake off, and I either didn’t know any better or didn’t think about it.
As Mitch Hedberg observed, it’s not really an emergency brake - it’s an emergency make-the-car-smell-funny lever.
I never bothered messing around with the parking brake until I lived in my previous apartment, because my parking space was on quite a slope. And I don’t seem to recall an enormous number of times that I left it engaged as I hit the gas.
I always always always use the parking brake when I park, and when I ride with friends who don’t, it creeps me out how the car bounces back and forth a little when I get out of the car. A friend once parked in my sloped driveway, and a few minutes later we heard her car slam into the tree across the street. I guess she had not used the parking brake AND left the car in neutral.
One day I parked my car in the parking lot and went up to the second-floor office where I worked. It was early and the lot was mostly empty. I happened to glance out the window and saw my car slowly rolling across the lot. It was an automatic, but like the person in the previous post, I guess I left it in neutral and didn’t engage the parking brake. I flew down the stairs and outside. Fortunately the car had come to a gentle stop against a curb. I have always used the parking brake since that day. The end.
Some years ago, I heard a loud thud, and my next door neighbor scream my name. I went running out of the house and saw that she had stepped out of her car when it was in reverse, not park, and it dragged her (with one leg out of the car, and her body caught in the seat belt) in a large semi-circle, backwards, until it crashed into her block fence. She was badly scratched, but otherwise uninjured. Clearly, this wouldn’t have happened if her parking brake was set.
Would it have happened if the car was in park, not reverse?
I’m guessing in @beowulff’s anecdote the car would not have rolled in park, but would roll in drive, reverse, or neutral. Someone else correct me if that’s wrong.
Even when my car is in park now, I still use the parking brake. Belt and braces, eh?
This is one of the things I’ve 
at. I mean, I can understand there is no need for even simulating the classic linear lever configuration (since all the selector is is a pointer for an electronic actuator), but I also do appreciate some mimetic design conventions being maintained across platforms just so the customer doesn’t sit there at the Avis lot for 20 minutes trying to decypher how does this blasted thing work.
I’m not fond of this particular misfeature either. For exactly the reasons you state.