It’s become a subgenre of documentaries, films capturing the last days of a beloved book store, video emporium, bar, restaurant, porn seller or record shop.

We meet the staff, hear the history, learn just what the place has meant to its customers — if there are some famous “regulars,” more the better.

At some point, some staffer will say something like, “Before the Internet, before iPhones, people trusted other people” when it came to picking out what to listen to, read or watch.

That’s a direct quote from “Other Music,” a documentary about the last days of New York’s East Village hipster hangout “cool” record store that hung around for 21 years.

Set up right across the street from a big Tower Records chain store, it outlasted all the chains by concentrating on the “new” and the “reissued,” the more obscure the better. Run by a staff of “curators” with mythic “High Fidelity” “encyclopedic knowledge” of popular music in general, its many genres and their vast array of choices in particular, it comes off as one of those places that made it into tourists guides in their “Only in New York” section.

The film gives you a feel for what made the place special, its hand-scribbled category name cards — “Kraut Rock,” “Decadanse,” “Out,” “In,” “Then” (reissues of music by musicians no longer performing) — and hand-written note-card “reviews” and passionate testimonials for new music.

In-store shows were another specialty. You could catch TV on the Radio, The National, Yeah Yeah Yeahs or the reclusive Gary Wilson live, on occasion.

A wildly-diverse staff of part-timers ensured the store was known for its catholic tastes — vintage country to new hip hop, every variation and subgenre of reggae known to humanity, punk.

No, you weren’t likely to find Adele and Lady Gaga and Stevie Ray Vaughn’s Greatest Hits. But that’s what the big corporate box store across the street was for.

Blossom Toes? William Basinski’s post-9/11 “Disintegration Loops?” “Italian psyche bands” and Ex Cops? Sure, right over here.

Celebrity fans like Benicio Del Toro and Jason Schwartzman sing the store’s praises, even as Schwartzman raises a humorous eyebrow at “the snobbery factor” associated with many an indie record store, especially present in one in NYC.

The site-specifics separate these documentaries from one another, while what they share — all of them — is sentimentality over the store or type of store that the digital age and Amazon have killed.

Five years ago I reviewed “All Things Must Pass,”about the rise and fall of Tower Records, for instance. Even the big box stores and Blockbuster Video warrant documenting as they disappear from the landscape. A store only around 21 years barely merits — in strict longevity terms — a documentary.

The only thing that “Other Music” does differently from the scores of “last days of a dying business” docs preceding it is showing us the day AFTER the emotional “last day in business” scene. Cleaning up your rented storefront is the least romantic but maybe the saddest part of such a retail “death.” “Ghosts” of records that once hung on the walls, the wear patterns on the floor paint that show where customers gravitated the most are nice details that make this generic doc-about-a-dying-biz at least a little more interesting than the legions of genre docs that preceded it.

MPAA Rating: unrated, a little profanity

Cast: Chris Vanderloo, Josh Madell, Lydia Vanderloo, Dawn Madell, Tunde Adebimpe, Jason Schwartzman and Benicio Del Toro

Credits: Directed by Puloma Basu, Rob Hatch-Miller. A Factory 25 release.

Running time: 1:23