I don’t have much experience with this, so please help me here. How does the wait staff at a crowded bar (including people standing around drinking and/or dancing) keep track of who owes what?
They take your credit card and hold it for you until you’re done drinking. When you ask for another or if it’s a different bartender they ask your name and change appropriately.
Either you set up a tab (they hold your credit card) or you pay as you go.
Or, they create a tab without a credit card. At the breweries/bars I frequent, that’s how “the regulars” pay. That way you can use a credit card to pay the food truck.
And they don’t rely on their memories. If necessary, they’ll have a little booklet to write it down in.
Yeah, it’s basically “pay as you go” or “open a tab.”
The culture of the bar and the nature of the clientele will often influence how it’s handled.
Real dive bars often default to “pay as you go” for everyone who doesn’t request a tab, and at those places unless you are a “known regular” they will usually ask for a credit card to “hold” the tab. This is not because they can’t track it any other way, but essentially because dive bars have a lot of customers who frequent them who they frankly don’t trust to settle up otherwise.
If you’re sitting at a restaurant’s bar eating a meal, and ordering drinks with it, in maybe a normal quality full-service restaurant they will generally track your drinks with the meal and everything else–it is unusual in scenarios like that for them to ask for a credit card. These are places that are more middle-class dinner destinations and dining and dashing is typically less of a concern. When I’ve done business travel in the past I’ve often ran up decently large bills at bars like this and you’re largely just trusted to settle up even though they don’t know you (but that’s a risk these businesses generally assume anyway–it is atypical for a restaurant to ask for you to pay in advance or secure your meal with a credit card, while dining and dashing is a thing, the risk profile for that at a place serving say, $30-50 per customer dinners is a lot different than a dive bar mostly serving cheap beer and well liquor.)
“Nicer” bars that aren’t part of a restaurant, but aren’t the sort of place where you’re mopping up blood and piss on the regular, do various blends of all of the above. A lot of them will let you open a tab on your “name” only, and they trust you to settle up. Some use the credit card system. The mechanics of them tracking your tab varies–old school is they have a little book or some paper slips they actually mark your drinks on and settle up with you at the end. If they’re requesting credit cards, they will sometimes paperclip the card to a slip of paper, and track it like that, and then run the card at the end.
POS systems have changed a lot over the years, as have credit card machines, the card paperclipped to a slip of paper thing was done because they didn’t want to run your card until the end of the night, because otherwise they would have to run it multiple times.
Newer POS systems they can actually scan your card in at the beginning of the night and hold it in an ‘open order’ and add your drinks to that order and close you out at the end. With these systems they can return the physical card to you right away and still charge you afterward. These systems also will let them open an order and give it a customer name without a card, and track it in the POS system, and when they settle up they’ll need your cash / card at that point.
The old Cheers system of a “running tab” that carries over from night to night has been a tad unrealistic even since the 1970s when I started frequenting bars. I’m not saying in all my time on a bar stool (which is significant) I’ve never ran into a place that actually did have Norm style running tabs, but even in the examples I can remember where this occurred it was always for very well known regulars only, and was discouraged even then.
At my local pub, some of the regulars drink particular types of bottled beer, and the staff actually have cups set up near the cash area, in which they just toss the bottle caps. They figure out the bill by counting the caps at the end of the night. They know who owns each one because in some cases, the person is literally the only one who ever orders that type of beer.
This has been my experience too, I do wonder about the risks though of mixed up charges and cc theft and how do they keep it all straight and secure at the till?
It’s not usual in the UK (or at least not in the big cities) to "put it on the slate’ in a bar - you’d have to be a trusted local. I have seen bars on the Continent where they had a slip on a hook for each person sitting at a bar, where they noted what that customer had had: but if you weren’t at the bar, it was PAYG (and I’d imagine the "local regular rule applied).
In restaurants the waiter would have a note of which table had had what, but these days it’s quite often electronified, as between communicating the order to the kitchen and to the till, and paying by card. And there are systems for doing something similar in bars.
A type of pay as you go is to just leave a pile of cash on the bar at your seat. Getting a new drink can just a subtle gesture away with a ‘When you get around to it’ understanding. Tips go closer to the bartender’s side. Obviously, there needs to be a comfort level that no one is stealing.
Yep, a particular type of dive bar has a lot of middle aged men with little stacks of cash sitting in front of their “spot” at the bar.
In my dive bar the bartender and waiters know the regulars and start preparing their drink when they see them pull up in the parking lot. Tabs are tracked on the POS register. New folks get a nickname and a tab on the POS system as well. Some of the nicknames can be inventive to say the least, offensive to say the most. They don’t deny anyone a tab.
Everyone knows who the new people are, they are being watched and spoken to by the entire regular crowd as well as the staff. You don’t want to deal with Dive Bar justice.
At a bar I’ve been in, a “regular” constantly over consumed and caused problems. Instead of 86ing him, they came up with a different plan. Anytime “BudLight Billy” (his name) came in, the bartender would put 9 Bud Lights in one area. He could drink those 9 beers, then he was shutoff.
Heh. I used to call the bar when I was five minutes away, and let the bartender know I was coming. At the time I drank Scotch. She’d make my drink and place it at the spot where she thought I’d like to sit. It was great. Then the bar burnt down. 
I wouldn’t necessarily consider that cause-and-effect. 
I assume they mostly use the same system restaurants use to keep track of who ordered what. That is, in most cases, they write it down, either on a slip of paper or in their computer system.
Under the Licensing Act 1964 pubs were not allowed to sell alcohol on credit. This was repealed by the Licensing Act 2003 and, since 24th November 2005, credit sales of alcohol can be made.
In most cases, they will swipe a card and add up all the purchases during the session. When they first swipe the card, they may “reserve” enough to cover likely expenditure (£100?) in the same way that a hotel will.
Of course, even before the changes, regulars might have an unofficial tab, but that wasn’t common. To misquote Shakespeare - “Neither borrower nor lender be for loan oft loses both itself and friend.”
Another cool thing about running a tab, if you are a regular who tips well, is that the bartender will run your card at a minute before happy hour ends. So, lets say you are there from 4 - 6. Happy hour is 5 - 6. Bartender will keep track of your drinks but not enter them into the POS. At 5:58 she’ll enter them all, making everything Happy Hour prices.
The sports bar that I go to rings every item up as you go and places the current tab in an empty tall glass in front of you.
I …Hey!
Something I forgot to add (beside the word ‘be’ in the second sentence) is that these places are often cash only.
Yeah the clue is in the name:“Tab”. Short for tabulation. they write it down.
Everywhere I’ve been that doesn’t take a credit card upfront keeps a record, almost everywhere other the diveyish dive bar does it on computer nowadays.