I am not Brad, nor any of the copyright holders, nor a copyright lawyer. But I am an asshole with an opinion, and this is the internet, so.
Your friend would not be selling the comics, distributing them widely (the reproductions would remain in one place), incorporating them in another work (they're in the lobby, not on stage), nor using them to promote that work (again, in the lobby, not in the newspaper ads). (You could make arguments for some of these, maybe, but I don't think they'd be strong ones.) So I think she's in the clear.
What about the other comics she's posting: were they all contributed by their authors, or did she clip them out of the Sunday paper? If the latter, it's hard to see how using the comic above would be any different, from a copyright perspective.
I don't think any of my own comics would fit the bill.
---
The what mentioned above is total fiction. Please don't take it seriously!
