Where do you stand on cash bars at weddings?

The price of beer at weddings seems to be going up these days. I’ve been to dry weddings, wine-only weddings, and those where the liquor buy was likely what it would take to kill Motley Crue.

Besides a potential hall, the bar can obliterate a wedding budget, based on the number of people coming and the drinking habits of said guests. Over the past few years, cash bars seem to have lost some of the stigma (especially if beer and wine are free), in as much as food trucks are standing in for more traditional caterers.

Is a cash bar a reality of the economy or should it be avoided at all costs?