Lunch spending survey on website (© Visa, Inc.)
Going out for lunch is either a necessary expense to preserve one's sanity or a fool's errand driven by laziness and insufficient respect for leftovers, depending on just how satisfied you are with your job.

Admittedly, just being able to swipe a card and eat makes it a lot easier, but that also makes those meals add up. A survey of 1,005 U.S. workers conducted by Visa (V) found that 70% of them go out for lunch and spend an average of $936 a year doing so. That doesn't count runs to Starbucks (SBUX) or Dunkin' Donuts (DNKN) for coffee or trips to the vending machine or newsstand. The figure is just straight-up lunch.

U.S. workers go out an average of about twice a week and keep it to $10 per outing, which is a whole lot easier to do when your office isn't surrounded by eateries or food trucks. However, the regional differences in spending have little to do with cuisine and, seemingly, a whole lot more to do with weather and cost.

Lunch spending survey on website (© Visa, Inc.)
Midwesterners are in the middle of the pack, with about 1.7 lunch trips a week, but they spend only $8.90 per meal. Northeasterners head out of the office a relatively scant 1.5 times a week -- but spend more than $11.40 every time they do. Westerners get help from the food trucks when sticking to the national average of $10 per meal for the 1.8 times a week they head out. And Southerners take advantage of their climate by going out twice a week and spending a whopping $20 each time.

That's still less than the 1% of all Americans who spend $50 per lunch, or $5,000 a year. We realize that sometimes a client needs to be impressed or that your lunch place of choice gets upgraded as you climb the company ranks. But the Visa survey indicates that it isn't always the folks in the corner offices spending their hour slicing up a steak at Delmonico's.

Those who said they make less than $25,000 per year spent more per meal, at $11.70, than those in any other income bracket. By contrast, those earning more than $50,000 per year spent an average of $9.60 per meal. That's a 22% swing between the haves and have-nots.

However, the smartest folks in the survey just might be the 30% who don't eat lunch out at all. If you can save almost $1,000 a year by brown-bagging it (or fasting), maybe that sub or kebab can wait.

More on moneyNOW