There is a post on the Budget Board about only having wine and beer. Which is completely fine.
One of the posters said
"i think it depends on the type of crowd your inviting too. if everyone is 40 or older i think you can get away fine with a dry wedding. if ur like us though and over half of your guest list is 30 or under, if you ain't havin an open bar you might as well not have a reception at all. just the way it is! "
I had no idea 40 was the magic age when people stopped drinking at social situations. Honestly the older you get the more sophisticated your tastes tend to become. So people in the 40's are more apt to want the liquor instead of beer. (but again hosting beer and wine is completely acceptable)
What differentiates an average host and a great host is anticipating unexpressed needs and wants of their guests. Just because the want/need is not expressed, doesn't mean it wouldn't be appreciated.