Why do people walk to a business they’re not sure is open and look through windows, look for signs, stroll back and forth, but not just try the dang door? Sometimes they even check the “hours” sign and their watch several times. I just watched a couple go through the routine this morning at Central Perk in El Cerrito, CA. They both shaded their eyes against the window and had a good look. They finally gave up without ever touching the door.
In fact, if I walk up, people will stand back and let me try the door. 
Seems to me that if the door is unlocked, the place is open. If locked, they’re closed.
Simple.
I see people do this dance very often.
(Add “shakehead” smiley here)
Peace,
mangeorge
On the flipside, have you ever noticed how many people come up to a closed business and feel the need to tug on the (locked) door, even if there are already a dozen people standing around, clearly waiting for it to open?
Oh yeah.
Same for elevator and ped crossing buttons. Some will swear that the controls count the pushes and hurry when there are many, so they push it repeatedly.
I work in a building that was designed to be a funeral parlor and would make a damn good haunted house. Several times people have come here when the building is unlocked and I am inside only to call the agents on their cell phone and ask why we are closed?
I can’t figure that out. The door is unlocked, but the place doesn’t “look” open.
If I was designing them, I’d make it so they would hurry up if pushed repeatedly. But I wouldn’t tell anyone.
You need an “open” sign.
There’s a convenience store near where I live that starts turning off their lights well before closing time… but they leave the bright neon “open” sign on so people know from a distance that the place is in fact open.
I told a chemist at work that if pressed three times. them pause, then twice, the car would come express. I demonstrated and the car did indeed show up soon. Coincidence, of course, but I’ll bet he’s still trying it. 
Chemists don’t spend a lot of time in the real world.
I have walked into businesses through open doors only to be told that they’re closed.
I should have limited the OP to retail business. Like stores and fast food, etc.
Still, what you say could happen. Generally though, the (teenage 
) enployees have the doors locked at least ten seconds early. I don’t blame them, either.
We were having the carpets steam-cleaned in our bookstore. All of the shelving was moved out of the front half of the store. Boxes were stacked in the front window. There was a steam-cleaning truck parked in front, and several large hoses were running through the front door. The door was open (for ventilation), with a large fan blocking most of the entrance. The remainder of the entrance was blocked by a strategically-placed chair. There was a “closed” sign in front. Almost all of the lights were turned off.
Not one, but TWO DIFFERENT PEOPLE at two different times pushed the chair out of the way, walked across the wet carpets (stepping over the cleaner’s hoses) and started browsing through the shelves in the back of the store.
You weren’t one of them, were you, Duck?
Perhaps they are afraid that if they jostle the doors after clsoing time all sorts of alarms will go off?
Brian
Nah, that would be fun.
My favorites are when a store closes at, say, 9pm, there is always one jerk off banging on the front door, claiming that by HIS watch it is only 8:58 and demands to be let in…
Don’t do it. It’s a slippery slope. Everyone will want in.
Truth is, I think it’s pretty rude to demand that someone who’s done for the day and want’s to go home should grant you special favor at their own detriment.
Special favor?
Asshole customer: Your sign clearly states that you close at 9pm, and it is only 8:58. You must let me in or I can sue you for (drumroll) false advertising!!! 
After the riot that nearly started outside of the costume store I worked at last Halloween when a customer showed up 20 minutes after our closing time and was outraged that he couldn’t shop for costumes even though we were still milling about, at the end of which we got death threats and needed police escorts to our cars, I’m not so worried about people neglecting to try the door.
A few weeks ago I was at work, about an hour before we were open I had walked out the front door to get the mail. I watched a lady walk up to the front door (she hadn’t seen me come out). I watched her as she notcied the neon open sign was off, I saw her move her head and notice a sign that said closed, I watched her as she peered inside and had to be able to tell we were still setting up and I watched her as she looked at the hours and then checked her watch. I also watched her try the front door, and since I had just walked out, it was unlocked and she decided that we were open…I guess we are now.
But I only want a gallon of milk.
Most of my employees understand that even though she’s just a little old lady and she only wants a gallon of milk, it will mean they’ll now be at work for an extra twenty minutes while she wanders around the store. She’ll also be the customer who has to take her time and look at everything. Then they understand why I keep telling them, once you lock the door, you don’t unlock it for anyone for any reason, even if it’s a little old lady who just wants a gallon of milk.
But they all have to learn for themselves.
The funny thing is, the reason I have that rule is becuase I’m concerned they’re going to get robbed at night after close someday when they let someone in. I don’t care if it’s a little old lady, how do you know there isn’t a big scary guy with a gun to her back that’s going to walk in when you unlock the door? Telling them that doens’t work. But if I tell them that they might wind up at work for an extra 20 minutes, that does the trick.
My brother used to have a hardware store. Someone pounded on the door after he closed and waved a bolt in the air, pointing at it. My brother let him in, since he just needed the one bolt, and got a gun in his face.
Luckily, he wasn’t hurt, but the guy cleaned out the register and the safe.
How would I know if any of those idiots actually tried the door before I got there?