This is something that always comes up with visitors to Spain. A friend has recently come to visit and in addition to noticing my food shopping procrastination, she made me realize that we eat at funny times.
We don't eat Spanish style but after living here so long and of course dealing with the weather the same as everyone else, we have inadvertently adapted to the food schedule.
The system as I, a foreigner, understand it in Spain is generally eating five times a day. It goes something like this:
Breakfast: maybe a cup of coffee, or a cigarette, or both. Juice and a piece of toast if you're all into it.
A toast favorite of mine here is pan tomate: toasted left over bagette bread smeared with puré of fresh tomatoe, olive oil, and sea salt.
Around 10:30-11am. It's break time. I can't seem to get a firm grasp on what this is called in Spain. Almuerzo is a possibility but some say otherwise. It is not uncommon for everyone to go get a coffee from an office environment around this time and eat something small. It is very common to see people who work manually sitting in the shade or on a sidewalk eating a bocadillo (sandwich on bagette bread) and drinking wine or beer or coke. It's a snack to get you through til lunch.
2pm Comida. In the Madrid area, this is just referred to as Comida maybe different in other parts. This is normally a three course lunch. On weekdays this is a very affordable and filling option. Last week I paid 8 Euros for: course 1 - cannelones; course 2 - skirt steak and fries; course 3 - an ice cream cone, drink included. It's sort of stick to your ribs physical worker food out in the villages where we are at. In the city a few minutes away, sometime it has more finesse but it's always the same structure. This is traditionally the big meal of the day. Children are released from school to go home and eat big and they come back at 4:30 or so which makes for a challenging day for working parents and a lot of grandparent involvement or paying the school to keep the kids for this time frame. After this would be your nap if you take one, not everyone does, and many people are too far away from home to go back anyway.
5-8 pm is merienda. Again snack time but more commonly this is something sweet. A donut or tortitas: that is American style pancakes with chocolate syrup and whip cream. This is the only time of day McDonald's serves pancakes here. People generally make sure kids get something during this time frame.
Dinner, well that depends. I understand that you might feed the kids here at 8 or 8:30pm. Restaurants do not open for dinner until 8, 8:30 or 9pm depending on their preference. I've entered a restaurant at 7:50pm and been told to come back later.
For Valentine's day one year, we left our house at 7:30pm, arrived, were seated and ate our dinner as the only patrons in the restaurant. At 9pm when we were leaving, a few couples were coming in. A fancy dinner out would probably be scheduled at 10pm or perhaps 11pm.
The next question every American asks is how do they sleep with all that food on their stomach. I have no idea. I do know people stay up later here generally. Even Spaniards sometimes admit it's not good for you to eat so late.
If they are eating at home, this 9-10pm meal is something lighter, not a big three course meal. A Spanish tortilla for instance would be a dinner. It's like an egg and potato omelet but made in a flat pan shape which is a fine art here.
I usually do eat breakfast. Mother raised me to eat something before I left the house. I don't do 10:30 snack/almuerzo though on occasion will eat a cookie if I'm starving around 11am. We eat lunch in the office between 1:30 and 2 usually, rarely do we go out for the three course meal. It takes a long time and even though affordable doesn't meet our budget.
I try not to eat anything after work around 6pm but if I'm starving I might have a snack. Dinner without air conditioning in a summer of 100+F at times got later and later. We ate consistently at 8pm but often it drifted into 9pm. Now that the weather is cooling, we might eat a little earlier. I like the free time aspect when I arrive home and often write then, rather than "starting dinner," so it's not going to get too much earlier than 8pm.
When we are home in the USA and someone wants to beat the crowd to a restaurant at say 5:30pm -- it sort of gives me reverse culture shock. It seems like eating a late lunch to me. Funny what you get used to without even knowing it.