I believe the days of 1/2 bottle of wine died a long time ago. There is also a limit now on spend, which is fairly unrealistic to put it mildly!
I have a sneaking suspicion I know what event forced the change.
An Army IPT at AbbeyWood had a very small project team who needed to host a bidders' conference. Only half a dozen needed to go (3 Army, 3 CS), plus reps from the 3 bidders. It was scheduled for 4 hours max in an ABW conference room.
The IPT's Commercial Manager insisted that the whole IPT attend and it be at an Army base in Wiltshire. Even so, 4 hours max so no overnighters needed. It was less than a 2 hour drive.
They block booked 2 hotels and the entire team was on a 3 line whip to attend an IPT "dinner" the evening before.
Most retired early. The rest, led by the Finance Manager, stayed and worked their way through the wine list on the MoD credit card. Their theory was that if there were 60 or so on expenses, that meant 30 bottles, whoever drank it. This was shared between 4 or 5 and they were found blotto the next morning when the cleaners arrived at 0500. They had no interest in the conference, so went to bed and didn't attend. The IPT leader (senior Army officer) signed the chit.