Coffee and Cigarettes in it's most complete form was released after Lost in Translation and The Royal Tenenbaums. I believe The Life Aquatic came out around the same time though. The fact that Broken Flowers is being shown at Cinemark & Lowes does not equal mainstream either, since all the other movie mentioned above also had wide release runs in the top ten theatre chains. I can give you a very long list of movies that we ran at my theatre (a cinemark) that were critical darlings but commercial flops.
While on the subject, The Royal Tenenbaums and The Life Aquatic were not "mainstream". Lost in Translation came close, but it was because of a great deal of hype and publicity from Murray's camp in an effort to get the guy the oscar that he really does deserve... hype of the sort that rarely ever pans out. Want proof (aside from the fact that he still doesn't have an oscar)? Go ask a hundred people if they saw lost in translation. You'd be surprised how few people say yes. Now ask those that HAVE seen it if they liked it. You'd be surprised how many people did NOT like it. fyi - I have not asked 100 people these questions, but I have overheard several hundreds of people conversing about the movie as they exit the auditorium. I would say a majority of the comments contained any or all of the phrases "boring, refund, fell asleep, worst movie ever" etc etc.
Bill Murray's popularity hasn't really grown in the mainstream arena over the last couple years. He has garnered a great deal of critical acclaim because of the roles he has chosen to play, but his name in the cast does not guarantee a mainstream success.
Now let's compare and contrast. Ben Affleck has been in a ton of bad movies. Too many for the few good ones he's done to make up for. Movies that were SO bad that he really should have been booted from the actors guild and banished to some uncharted desert isle... and people LOVE the guy. They can't get enough of him. Really talented actors like Johnny Depp and Bill Murray make a whole string of good movies, but unless they are some gazzilion-dollar budget film produced by Bruckheimer or Bay, no one really cares.
This all brings me back to my original point: big names do not equal big numbers. Directors like Jim Jarmusch, Wes Anderson and Sophia Coppola have made enough movies with enough big names that, if that logic WERE true, would have put them into the upper eschelon of film makers. Instead, we have to let morons like Michael Bay, Tom Cruise and John Travolta get the mainstream with mindless drivel as opposed to quality, thought provoking movies.
It sucks, but it's the sad truth.