You're not going to go through the bill and start doing the, You had an appetizer for $7.99 and dinner was 15.99, you had 3 glasses of wine.......".
Um, we do this all the time in NYC too. But then again, we're know for being rude, upfront & in your face.
We just treat it as a business transaction - which it is. Why are people making so much more over paying a bill? The bill just goes around the table. People look at it & pull out their wallets & pay for their share. If they had an appetizer for $7.99 and dinner was 15.99, and had 3 glasses of wine, they'd pay for
all of that. Plus tip. If you ordered it, you pay for it. THAT'S fair.
There have been too many times many of us have gotten screwed in "Let's split the bill evenly." Why should someone who only ordered a $5 salad pay for someone else's alcohol consumption and end up paying $25 a head, instead?

Or a vegetarian pay for someone else's steak?
The OP doesn't have to point out she's paying for 3 people. She'd simply, quietly add up her amount & lay out $75 or whatever.

No big deal. Then the bill gets passed to the next paying person. That person hands over their amount to the person collecting the money.
People are usually chatting during all this, and don't pay attention till the bill is in front of them. They don't look around and say, "Hey! OP, you paid for three people.
The money gets counted right in front of everybody to make sure we've got the right amount. Again we simply treat it as a business transaction. (We've also gotten screwed by someone not leaving enough, either intentionally or by miscalculating and have been left paying more than our share.)
If it's off by a lot, that means someone forgot a drink or appetizer. Usually you can tell the amount, like $13. Then someone looks at the bill again & says "Oh yeah, I had the calamari. It tasted off, so I didn't finish it & forgot I ordered it." No shame, they just toss in the missing dollars. If there's not enough for a tip, everyone forks over another dollar or two.
If one person wants to pay by credit card, we hand all the cash over to that person once we know the amount is correct. Usually the waitress gets the tip in cash.
It's great when everyone put in more than enough and we all know the waitress is getting a nice big tip.
