My experience in mgmt. consulting was the same. We had an office party with liquor almost every Friday starting at 3 or 4:00, and everyone would go and have a few and then go back to their desks and continue working. Or not even stay at the party but just bring their drinks back to their desks and keep on working. On dinners at night out with the client or the team, we absolutely drank anything we wanted. Very often a group (20-40 people) would go out for drinks after work and a partner would pick up the tab for everyone.
Re what Una said about dress codes. When I started in 1995, the rule against women wearing pants had only recently been abolished, because a female partner made a great big noisy fuss about it. Women still had to wear pantyhose as late as 1999, when I left.
I work for an intelligence agency where illegal drug use results in the swift loss of one’s security clearance. In fact, it used to be the case that smoking grass even one time, years before applying, prevented you from getting a clearance.
So when I started work here in 1986, I found it amusing that there were beer vending machines in the cafeteria. They were around for a couple more years, and were removed around the same time as the sweeping bans on workplace smoking.
According to colleagues of mine who worked here in the 1970s, it was no big deal to keep alcohol in your desk. You didn’t get sloshed every morning, but if you had an airline bottle of whiskey with lunch at your desk once in a while, nobody cared.