The quality of the image is a big part of why film has been preferred for so long. This Wikipedia article (http://en.wikipedia.org/wiki/Digital_versus_film_photography) really outlines well the technical advantages.
However, you asked about favoritism between the two formats. I think another consideration is cost, familiarity, and accessibility. When I got my bachelor's in film/video in the late 1990s, I focused on learning how to shoot video, rather than 16mm, because I knew eventually, digital video would supplant film. I thought something like this was going to happen: that digital imaging would make filmmaking far more accessible to everyone. Since I was also a computer nerd and more of an early adopter than I then realized, I overestimated how quickly this transition would take place, both at my school (where only a favored few were given access to computers with the horsepower to render Adobe Premiere, or allowed to use our singular Avid editor) and in the world at large. Meanwhile, my classmates who were shooting traditional film were already able to produce a much, much better looking product, and over time some of them stuck with film, because that's simply how they were trained and most comfortable.
By the same token, the time I've spent producing corporate video, taught me about the inertia that can crop up, when standardization of equipment plays a role. For instance, my former workplace only switched from SD to HD cameras about two years ago, and absolutely, we had the budget to make that change a lot earlier. Upgrading was a difficult decision that had to be planned out over years. Consider that it's one thing to pick a tool that allows you to edit either digitized film or digital video (FCP, Premiere, Avid), and invest in it; it's another thing to decide you're going to switch from traditional film cameras to digital film cameras. What will it cost you in terms of a learning curve for your production personnel? What other equipment might you have to replace? How will it change your workflow?
Now, I learned a ton from a former colleague that recently retired, in his mid-60s; he was a consumate cameraman who had been working in film and TV longer than I've been alive. He could and did handle change, and move from film to SD, to HD, but still, there were areas relating to digital video he just didn't care to delve into if he didn't have to. That doesn't make him an old fogey, but someone who carefully considered the payoff of investing his time in learning new things. Because he had so many years of experience, the vice-president of our organization considered him to be the most important decision-maker about the direction of our equipment; he was very conservative. Now transfer that to thousands of other workplaces where there's not a lot of discretionary cash to gamble on the next big thing.
And, as late as 7 years ago, copies of "Film School Confidential" were available, a book that outlined the atmosphere and equipment at the major film schools offering MFAs. Many schools were described as having a limited amount of film equipment that students would compete over; at some top schools, only a handful of students would create "calling card" films in the second or third years, with others relegated to crewing. I can't be sure, but I believe these schools had similar attitudes to the new technology, as my alma mater did: rather than burning the budget yearly or every other year on the newest digital cameras which would become obsolete rapidly, or didn't quite have the dynamic range users were wanting, many of these schools continued to stick with traditional film equipment - cameras, Moviolas, etc - for the vast majority of their students. Just as my former employers hung on with standard definition cameras as long as they could.
And inertia also plays a role when you consider the people who are training young filmmakers in more formal, traditional programs. I actually went to a less traditional program that emphasized documentary and experimental filmmaking, but some of my former professors apparently still prefer film, or only moved over to digital a few years ago, and that's not a surprise to me. Some folks decide they want to stick with what they know, and use that tool or format to refine their art. One of my old professors was at one time known for her "cutting edge" video art, but by the time I met her, I felt she was not at all open to new technology; the last I heard she was working on a documentary shot in the far more expensive, traditional film format, and she still has an AOL email address, for cripes' sake.