I think that the problem is that American Idiot is by a band that does have an audience and does have an appeal in seeing the show. However, it is a group that doesn't usually go to the the theatre and as a result can't really afford anything higher then rush tickets, maybe balcony. But, not full price or anything that would do substantially as far as the box office and the numbers are concerned. This, I think is the problem of putting a show on Broadway that is based on the album/music of a popular rock band. Sure, the fans of the band would love to see it. However, most wouldn't be able to go. However, I would like to applaud the show for getting people that wouldn't normally attend the theatre for going to see a show.
As far as Addams Family goes, I saw it on Wednesday night at the suggestion of a friend who was at both the final dress as well as the first preview. Now, keep in mind that she is someone who values her time and as a result never sees anything twice and left singing its praises. I loved it. My prediction with that show is that if it keeps running a year with the same numbers that it has now, then it might recoup before Nathan and Bebe leave. Therefor, if it does close soon after, it would close as a hit.
"If you try to shag my husband while I am still alive, I will shove the art of motorcycle maintenance up your rancid little Cu**. That's a good dear"
Tom Stoppard's Rock N Roll