The idea behind all the alcohol is to "lull them into a false sense of what a PhD program will really be like."
Well, I've never drunk as much alcohol as during my PhD, so it might not be far from the truth. Jokes apart, there's really no way to communicate what being a PhD student really is, because, apart from some rough generalizations, each student will live their PhD in their own personal way (e.g. I see my students getting stressed for things that, at the time, didn't stress me at all).
Now, a suggestion that we tried this year with the new bunch of PhD students. I don't know if it can work for you due to the different way of organizing the PhD programs.
We had 8 new PhD students (for our specific program) and we asked each of them to deliver a non-technical 15-min speech on their plans for the PhD, describing in which project(s) they were going to be involved, which courses they plan to attend, and if they planned to spend a period abroad. The speeches were delivered in front of the PhD program board and the advisors.
If the above is not applicable to your case, because maybe the students don't know yet what they are going to do, you may ask them to deliver a short(er) speech on their backgrounds and interests. I think it's important to let them present each other in front of the others.
In any case, make them speak before they get drunk.