A lot of restaurants in Spain have a little walk-up window that connects the street directly with the bar which obviates the need to even walk into a place to get your cortado or your quinto (a small 1/5 liter bottle of beer). So not only are there more bars per capita in Spain than any other place in the world, they make it even easier for you to get your shot of coffee or whatever suits your mood.
I first noticed bars with walk-up windows in Miami. At the time I thought it was a Cuban thing—which it is but its origin is Spanish. I had been to Spain a couple of times before I moved to South Florida but I didn't notice this feature in Spanish bars. There was a little café near my apartment in Florida that had one of these windows and I thought it was pretty cool. I have never seen one of these walk-up windows in Mexico, Peru, or Puerto Rico, and I've been to a lot of bars in Mexico, Peru, and Puerto Rico—the only other Spanish-speaking countries I have visited. Perhaps this aspect of Spanish life immigrated to other Latin American countries.
The whole notion of knocking back a quick shot of coffee at a walk-up window almost seems antithetical to the unhurried pace of life here, unhurried at least until people get behind the wheel of an automobile. If I were forced to explain the phenomena of the walk-up window, I would say that the services provided by bars are so important in the quotidian life of Spanish people that direct access to the street if sometimes necessary. It's like removing a buffer zone between citizens and espresso. I'm surprised that they don't have waiters with trays of espresso patrolling the sidewalks so people don't even have to stop walking to have a shot.
Depending on the weather, I usually prefer to sit at a table outside at a café or stand at the bar inside. This is an important part of every single day for me. If I am alone I use the time to read a book, a football paper, or a newspaper. I sometimes study my vocabulary lists or I study what is going on around me. If you are a tourist, bars provide the best place to connect with Spanish people, something that is true even if you aren't just passing through. If you are out to literally “rub elbows” with the locals, the walk-up window is the place to do it. Whenever I stop for a drink at one of these widows I always feel like I couldn't be more Spanish if I were wearing a matador's costume. I would love to have a picture of a matador at a walk-up window (to digress a bit, I saw a little boy the other day wearing a matador costume and it was so cute that I almost tinkled myself). The walk-up is also handy if you are on your bike and don't feel like locking it up to go inside.
Not every bar in Spain has a walk-up window. In fact, when I went out looking specifically for bars with this attribute I found a lot fewer of them than I thought I would. However, it seems like the bars that don´t have a window were just built wrong, with the bar being against a back wall away from the street instead of along the side of the place moving up to the sidewalk. If I ask an older person here about this I'm sure they will tell me that back in the good-old-days every bar had a walk-up. I actually had someone tell me the other day that there used to be a lot more bars in Spain than there are today. I can't see how that is even possible unless there used to be bars inside of other bars.
I'll probably never find out why the Spanish feel these windows are necessary and other people of other nations don't. Spanish people probably just feel that it is too much of a chore sometimes to walk inside of a bar to get a coffee. I mean, if you have to actually walk through a door you might as well cover the place in barbed wire or build a damn moat around the place. When you are walking the block and a half home from the market who needs the hassle of opening a stupid door just to get a beer?
It's not like there aren't millions of cars in Spain but walking is still a big part of city life. I have yet to see a drive-up window here and I hope that this never catches on—anything that keeps people inside their cars is a bad thing in my book. I'm sure that a walk-up bar window would be breaking about nine million laws in the U.S., although I have bought a cocktail at a drive-thru window in Montana years ago and even then it seemed like a disastrous idea. On the other hand, anything that caters to pedestrians is OK by me. What kind of culture are you looking for, walk-up or drive-thru?