What about seeing profs outside of school in a personal setting - say meeting for a coffee at the weekend?
I have a job as a prof for kids who are new to Australia and taking a prep year before entering a Queensland University. For most of these kids, it's all new to them and they are quite keen to learn about Australia and do 'normal Aussie things'. Some have hinted or asked what I do at the weekend.
Since I am more used to working with high school kids where it is just not a done thing and it seems that uni is different. Also, I can empathise with these kids, who are struggling with a new country and language and trying to find their way here.
No one at work seems to be able to give me a definite yes or no that this is a done thing.