When we write a story, the setting is the 6th man on our basketball team. It is the landscape where all of your action takes place and has very real effects on your characters. In a way, it is its own character.
Authors, if you choose to use a real place in your story, you need to do your research on that place. Someone who called that place home will inevitably read your story. If you haven't written a narrative true to that setting, that reader will know, will call you out on it--at least mentally--and from then on, they are reading a book. That reader is no longer immersed in your story because they know you're lying. Disbelief is no longer suspended.
So, as an author, you need to think about this. You need to make sure that not only are you writing from a place of truth as far as your characters are concerned, but you need to write from the truth about the place you use as your setting. And in the day and age of Google, you have no excuse not to give a shit about the devil in your details.
For fun, let's say that you're writing about Terre Haute, Indiana. Now, this is a smallish town in the armpit of Indiana. It's a college town and its most famous alumnus would be Larry Bird. This is the general knowledge that most people would have about this place--assuming you've heard of it in the first place. A quick Google search can bring up a map, the names of local businesses and the mascot of Indiana State University. You can pepper your manuscript with these things, thus thinking that you're writing about Terre Haute, but that doesn't make it authentic.
For starters, Terre Haute residents (aka Hautians) live under a constant brown cloud, a funk that can only be described as, "Ah, smells like Haute." Why? There's a paper mill there. The place reeks. Locals may not notice it after a while, but a visitor can't help but notice. Hell, when you're driving into town on I-70, you can literally see the brown cloud over the city center!
Other than the funk, there are 3 colleges in this town: Indiana State University, Rose Hulman Institute of Technology and St. Mary of the Woods. Very different student bodies, different curriculum and attitudes. This also means you have a transient population. This will shade a story depending on how your characters interact with locals.
I'm not sure why you would want to do this, but for fun let's say that for some reason you're having a car chase through the streets of The Haute. Anyone who has ever driven a circuit just around the ISU campus will tell you that the number of one-way streets in this town is insane. Damn near every other street is a one-way. So, if you look at Google Maps, glance at the street names and just pick where you're going to lead your pursuit, you need to pay attention or else your protagonist's ride will be going to wrong way up 9th.
If you're going to go to a bar in Terre Haute, they will probably have Champagne Velvet on tap. Sure, you can get other stuff, but CV is a local brew with its own claim to fame in the area. Look it up and you'll understand the caption above. Bonus points if you can tell me in the comments.
Also, the ISU campus has a railroad track on every. single. side. There are train tracks EVERYWHERE in Terre Haute. When I lived there, I'd talk on the phone with my friend Patt in Arizona and he'd always ask, "Christ do you live under an El?" because he could hear the trains. Seriously. So. Many. Trains. That car chase is probably going to get stalled by a goddamn train.
These might seem like insane details. You might think I'm nuts for saying you should know them. But, when you've got a real place on a map there are people who really live there. You need to know. Even a little place like Terre Haute, Indiana where people can't agree on how it's pronounced. (Terry Hut? Tear Hot?)
For the better part of 5 years, that was my home. If someone writes about it and doesn't include at least some of these above details, I'm going to call bullshit. I'm going to know that this person has never been there, talked to anyone who did live there. I'm going to think they just threw a dart at a map to choose their setting.
And this is just a little town! What if you want to write about one of the big names? Phoenix, Vegas, New Orleans? These places all have a national reputation, but there's more to them than that. If you can't go there and physically walk the streets, you need to spend days on Google maps. Use the street view. Talk to people. Socially network and figure out how you can write like resident, not just a tourist.