This just made me think:
one thing that would bug me about a hostel in the US is the liquor laws - 21 to drink!? there are a lot of backpackers out there between 18-21 and i wouldnt want to limit the market of the bar by excluding them, or having to be so uber-vigilant about checking ID in the bar.
In eight years, we never had the idea to check how old our guests are. I have just asked the receptionists of our 3 hostels (Wombats Vienna*2, Wombats Munich) to look up how old the last 100 persons who checked in are.
60 and older: 1
=> only 8% below US drinking age.
145 guys, 155 girls.
I am curious what it´s like in other hostels. Count!