The number worth having at the end of an event is per counter, not per site. What to count, where it comes from, and what a mismatch means.
Closing a venue down is mostly physical work - shutters, fridges, bins, cash - and the paperwork at the end of it tends to be one figure for the whole site. That figure is true and almost useless, because nothing can be done with it. It cannot tell you which counter was busier than anybody planned for, which one sold almost nothing, or which one was quietly failing to print for part of the evening.
The count worth doing is per station: how many tickets that counter printed, set against what that counter sold. Two numbers, one counter, repeated for each. It takes a few minutes a station and it is the only record that says anything specific about how the night actually ran. Kept from one event to the next, it also becomes the staffing plan for the next one.
The first number is tickets printed at that station - the paid orders that reached that counter and came out of its printer. The second is the sales attributed to that station in the order record. When ordering and printing are part of the same flow these two come from the same place and should agree exactly: an order that was paid for created a ticket, and that ticket belongs to one counter and no other.
If a station sold more than it printed, orders reached it that never came out as tickets. That is the one to chase, because it means somebody standing at that counter either waited on an order the staff could not see, or was served from a shouted instruction rather than a ticket. The causes are mundane - the roll ran out and nobody watched for the stripe, the printer lost power during a clean-down, the device sat switched off for part of the evening - and every one of them is easier to find at closing than to rediscover at the next event.
If a station printed more than it sold, the answer is usually reprints and test tickets. That is normal, and worth noting on the sheet as such so the gap is explained rather than carried forward as a question. A counter whose two numbers match every night is doing exactly what it should; the whole point of counting is to notice the night one of them stops matching.
Read the balance between stations as well, not only the agreement inside each one. A counter that takes a large share of the site's orders at every event is understaffed rather than popular, and one that takes almost none is usually hard to find, badly signed, or selling a menu that overlaps with the counter next to it.
The reason this gets skipped is that it falls at the worst moment of the night, so it has to be short enough to survive being last. One sheet a counter, two numbers on it, initialled by whoever worked there, collected on a single walk round the site.
None of this is accounting. It is how a venue finds out that a counter stopped working for half an evening, and how the vague sense that the far bar is always slammed turns into something a manager can staff against. Two figures a counter, written at the counter, and the sheets kept - one night's numbers describe one night, but six nights' numbers describe the venue.