All Quiet on the Western Front was released in the early days of cinema, and fandoms didn't exist back then like they do today. No one went to conventions cosplaying as Himmelstoss, and if you asked someone if the film had a Wikipedia entry, she'd ask, "You wikied a what now? Should I be concerned?"
But the film's fans do exist—even if they aren't having trench-themed weddings. Their rank consists mainly of film buffs, scholars, and historians, and they've done their best to promote the film to new generations of film fans.
Film critic Leonard Maltin has often praised the film and wrote program notes for its latest Blu-ray release. He also suggested Universal include the film's silent version, so audiences could compare both versions of the film—although he admits the film is a great experience either way you watch it (source).
Author Andrew Kelly wrote an entire book dedicated to its history. The American Film Institute placed All Quiet on its Top 10 Epics. It even held a spot on AFI's original 100 Greatest Movies list…but was bumped off in the updated version (source).
We'd complain, but have you seen that updated list? That's some stiff competition.
Yet the greatest act of fandom has to go to the Library of Congress. The organization included the film on its National Film Registry "to ensure the survival, conservation, and increased public availability of America's film heritage." Its Motion Picture Conservation Center then worked with extant copies to restore and reshape the film to be as close to Milestone's original cut as possible (source).
Chances are if you've seen the film today on DVD or Blu-ray, then this is the edition you've watched…ensuring the film can find new fans for another eighty-plus years.