"could send me a link to the census on movie viewership that shows how young the viewing audience for Boondock Saints is since it is "widely known" that this movie is favored by younger audiences."
Besides the fact that the industry unofficially classifies BS as "teen gore" you can go to its imdb.com ratings here:
http://www.imdb.com/title/tt0144117/ratings. These ratings are "weighted" (IMDb publishes weighted vote averages rather than raw data averages. Various filters are applied to the raw data in order to eliminate and reduce attempts at 'vote stuffing' by individuals more interested in changing the current rating of a movie than giving their true opinion of it). You will see that the two highest rated categories are males & females under 18 and Males under 18 which verifies the claim that BS is a teen targeted film.
"It was not realeased widely in America due to the poor timing (Columbine). It was not sent straight to DVD because it was a poor film...that generalization is painfully ignorant."
Yes, BS was pulled from theaters due to its violence (that reinforces my thoughts about it anyway), but the fact still remains that it was not screened for critics which is the distributor's means of "sneaking it under the radar."