Since the movie and 're-discovering" of Anvil by me..(I'm a guy in his late 30's who bought Metal On Metal when it came out in the 80's and have checked in on them from time to time since then), I see the fame arc going someting like this:
There will probably be a drop-off in concert attendance once the film is not fresh in the general public's minds..BUT there will be alot of NEW, REAL fans going through their back catalog and getting into the band for real, not just for the "oh,that band from the VH1 movie" kind of passing curiosity..
Look, it happened with Aerosmith in the early-mid 80's, Before they got clean/before hired songwriters came in/before 'Permanant Vacation' and the career ressurection with the Run DMC video..They couldn't get arrested..they were pretty much a washed up band that no one but the die-hards cared about anymore..Now, they are back 'on top'... even though that means they put out shitty records now and Stephen Tyler wants to just call it a day..they still sell more records/concert tickets than when they were putting out truly awesome shit like 'Draw The Line'.
My point is: The general public are a fickle bunch,whats 'hot' now never stays 'hot'. But its not them that Anvil are playing for anyway, its always been for the true fans..
Lips and Rob are guys in their 50's now, with families..This could be the last go-round for them..But at least they are wrapping things up on a high note..With some money in the bank at last.