Another 'how [tech company/product] is ruining [social norm]' thought piece.
We are not doing down-to-the-penny nonsense because that would be silly and we are not dunning our friends because that would be awful.
The only assholes are the ones who freeload often. venmo keeps everyone in check.
What is your neck of the woods, partner?
I don't know, maybe I just hang out with folks who take friendship with a degree of seriousness, but nobody I know would need to dun somebody in either our group or our extended group to pay their share. You grab the bill, you eyeball it for your stuff, you add twenty percent for tip, you're done.
If you try to freeload, you just wouldn't be invited again. Because friends don't do that, just as they don't send each other invoices.