Customers wait for their salads at Sweetgreen, a fast-casual salad chain. (Dixie D. Vereen/For The Washington Post)
Food reporter/columnist

We’ve all been there, whether at a fast-casual restaurant or a coffee shop: You walk up to the cashier, place an order and, next thing you know, the employee has flipped over the little white tablet, which now beams in your face, curious if you’d care to leave a tip. The tablet may even suggest amounts. It could be $1 on top of a $10 salad bowl. Or it could be 25 percent on a $23 bag of naturally processed single-origin beans, a tip that immediately raises the price of your coffee by $5.75.

You might stand there for a moment, filled with anxiety and confusion, as both the cashier and the customers behind you wait to see what kind of cheapskate you are. Then a thought or three race through your mind: What exactly am I tipping for? I have to stand in line to order. I have to pick up my own meal/drink, and I have to bus my own dishes. Why should I tip the same percentage that I would at a full-service restaurant when I get only a fraction of the attention?

They’re good questions and ones that I put to proprietors (or to the PR people of proprietors) who operate counter-service establishments. Their answers were not easy to sum up in one tidy declarative sentence. One said a tip is a show of support to the business and your desire to see it thrive. Another suggested tips incentivize counter-service employees to excel at their jobs. And several advised that tipping at the counter is similar to tipping at the table: You simply reward good customer service when you receive it.

Rob Sonderman, a partner and pitmaster at Federalist Pig in Adams Morgan, follows a rule of thumb on tipping: “Any job that you can otherwise perform for yourself, you should be tipping,” he says. This class of businesses includes everything from nail salons to restaurants (since, theoretically, most adults can feed themselves). “The people who are working in those kind of places are generally not paid extremely well. They often live and die by tips.”

All of these ideas sound relatively legit, but they don’t really address a nagging question: Do you need to tip on counter service because, like their counterparts at full-service restaurants, they’re not earning the full minimum wage?

At full-service restaurants in most states, waiters and waitresses earn a tipped minimum wage, which can run as low as $2.13 an hour. Both server and employer expect diners to cover the difference between the tipped minimum wage and whatever the regular minimum wage is in that restaurant’s jurisdiction (and if they don’t, the employer is required to do so). In the District, for example, the tipped minimum and the regular minimum wage will increase next month to $3.89 and $13.25 respectively, unless voters on June 19 pass Initiative 77, which would gradually eliminate the tipped minimum wage for servers and bartenders, who would earn $15 an hour by 2026.

A relevant question here is: Where along the minimum-wage spectrum do counter-service employees fall? They are not fine-dining servers who dote over customers, providing wine recommendations and carving birds tableside. No, counter-service employees are more like bartenders: Some do little more than take and hand out orders; others are professionals with fine-tuned skills and knowledge in a particular subject, such as coffee. Yet most counter-service employees — at least at the four places I checked into — do not rely heavily on tips for their salaries. Their employers tend to pay them a dollar or two below the regular minimum wage (usually during a training period) — or several dollars above it.

These two factors — your limited engagement with counter employees, and worker salaries that are pegged at the full-minimum wage or higher — would seem to let you off the hook in terms of tipping, right? You are not bound to that tacit pact found at most U.S. restaurants, where you are essentially required to help cover a server’s salary. But there’s another question you should ask yourself before making a final decision on whether to tip: Do you consider the minimum wage — or even $15 an hour — a living wage?

The answer to that question, of course, depends on where you live, not to mention how you live. GoBankingRates.com has calculated how much money you need to live comfortably in America’s 50 biggest cities. If you earn the current minimum wage in Washington — $12.50 an hour — and you work 40 hours a week for a full year, you’ll make $26,000. That annual salary is not even half the $80,273 that GoBankingRates claims you need to live comfortably in the District.

But then again, should customers feel responsible to help a business provide a living wage to its employees? Isn’t that the responsibility of the business itself? This, I think, is the crux of the argument. Take Starbucks, for instance. According to spokesman Reggie Borges, all Starbucks employees earn the full minimum wage, or more, in every market in which the chain operates. Workers also receive health benefits, stock grants and even college tuition credits. Starbucks, it’s worth noting, raked in $6 billion in revenue last quarter. The company’s financial health would appear to be robust.

Now compare that to Qualia Coffee in Petworth and Eckington, where staffers earn right around the D.C. minimum wage once they make it past the initial $10-an-hour training stage. These workers are not mere mudslingers, notes Joel Finkelstein, the owner of Qualia. They’re trained to know coffee — the different growing regions, the roast types, the flavor profiles — even if most customers don’t give a flip about any of it. Nearly half of his operating costs, Finkelstein says, goes to payroll. He really can’t raise salaries any higher and keep the business afloat. The owner is already running the shop, more or less, as a charity.

“I live pretty close to poverty level,” Finkelstein tells me. “I don’t make any money.” Every pay period, he says he takes home about $450.

Finkelstein continues the slog because he believes in Qualia’s mission: to introduce Washingtonians to new and interesting coffees while supporting growers around the world. Knowing this, would you tip his employees an extra buck or two to help Qualia maintain staff stability? To show your support for a local specialty roaster? To provide a measure of comfort to a dedicated employee as she prepares your morning cup?

The answer, it seems to me, is obvious. So is the process by which you determine to tip at a counter-service shop: Get to know the business. This isn’t a painstaking investigation. The knowledge comes naturally through repeat visits and casual conversations. If you believe in the business and its employees, support them with tips.

Have questions about cheap dining? Ask in the comments below, or email Tim Carman at tim.carman@washpost.com.