I see what you did here.

From IMDB.com:

Watchmen: When A Win May Be A Loss

Although it took in $55.2 million at the weekend box-office, the news for Warner Bros.' Watchmen wasn't all that good. After reports came in of heavy pre-opening ticket sales on Internet sites, a theater count of 3,611 and a screen count of about 7,500, analysts had expected it to come close to or even exceed the $71-million opening gross for the previous Zach Snyder fantasy thriller 300. Moreover, sales fell off precipitously on Saturday and Sunday (the movie took in almost half its gross on Friday, including midnight screenings), and some pundits saw the result as an indication that the movie's appeal was limited to young adults who were fans of the graphic novel on which it was based. (Warner Bros. said that 65 percent of the audience was male and 54 percent older than 25.) They predicted that the movie, which some said had cost as much as $200 million to produce, would take a big tumble next weekend.

Whoever thought that Watchmen would pull huge numbers is not bright. Watchmen isn't a comic book that's been around for decades with multiple iterations. It's not a franchise like Superman, Batman, or X-Men. It's one graphic novel. From the 80s. With limited readers. There are no generational ties with Watchmen. At least not to the extent of said comic books.

Trying to compare Watchmen to 300 isn't justified either. Same director, sure, but did movie heads compare Schindler's List to Jurassic Park just because they were directed by Steven? No. While 300 was a technical achievement, Watchmen isn't. There isn't anything groundbreaking in Watchmen; it's just another adaptation.

Also, Watchmen was presented as a superhero tale, very dark, and very violent. I would venture a guess to say the general populace saw the previews and thought, "Hmm. Looks like an X-Men rip-off movie. That's dumb."

Lack of identity with the characters and source material should have been the first clue to the movie heads. Throw in the non-Watchmen movie goers who don't really understand the theme, and you have more non-recommendations.