Pretty much, all the Irish/Scotttish/Celtic festivals I perform at here in the U.S. have liquor or beer sales.
Guinness, Murphy's are major sponsors at some, Miller, Coors at others.

The larger festivals such as Longs Peak in Colorado have at least three main tent stages, with subsidiary smaller stages. Sponsored by Murphy's (and formerly Guinness).

The Celtic Classic in Bethlehem, PA has at least 3 large tent stages and about 5 or 6 smaller ones. Sponsored by Coors.

Entertainment is on a rotation basis, with acts following each other on the hour.

Some festivals have a session tent, where the performers can jam with members of the public.

Usually at the larger festivals, the performers are housed in the same hotel, so the session would be in the hotel bar. And I've been in some mighty ones!

Seamus