Liberal media mecca The Huffington Post has a regular section devoted to celebrity. Most of the inane chatter about celebs that fills up your Facebook feed comes from those with liberal leanings as well.
Conservative outlets discuss celebrities as well, but the balance of lurid, not-so-newsworthy stories about folks you don't know is shifted more toward unknowns. Somebody who might be a part of your own local community -- the town drunk, the village idiot, the school slut, etc. If they're a celebrity, they're less likely to be one of long-lasting fame (or infamy), and more likely to be a one-hit wonder. COMA BABY LIVES!
Liberals also focus on the unknowns, but rather than read the occasional blurb about them in the NY Post, they require 24-hour connectivity. For example, today's schedule for the Bravo channel is all lurid reality TV programming, from 8am to 1am. And all those hours only cover four series, so that your familiarity with the characters of each one is done to death.
Whether liberal or conservative, certainly people who read news sites and tune in to character-based TV shows have an interest in people rather than things. Yet why are liberal people-people so obsessed with remote celebrities, while conservative people-people are curious about closer unknowns?
I think it gets down to liberals being more cerebral and oriented toward the abstract, and conservatives more corporeal and oriented toward experience. See some old posts here and here for evidence that this seems to be rooted in brain differences between the two groups.
If you're interested in what's going on in people's lives and relationships, but bristle with OCD fussiness when connecting (even indirectly) with real-life individuals, where can you turn to? Novels are one option. But they don't really update those things very often. Celebrity "news" to the rescue! The individuals are more distant, hypothetical, and intangible -- not rooted in your own community.
On the other hand, if you prefer to stay grounded in the real world and keep tabs on your broader community (even the more freakish ones), then you'll be drawn to one-off blurbs about the village idiot, town slut, etc.
I think this is also why the more advanced countries seem to be obsessing more and more over time with celebrities -- our brains are being selected for greater abstraction. And it also accounts for cycles within that long-term trend -- when people were more corporeal and rooted in experience and in their communities, oh I don't know, like back in the '80s, celebrity obsession was pretty minimal. In the more abstract and cerebral Millennial era, it's back to the mid-century obsession with Hollywood celebrities.
It's important to emphasize that liberals or cerebral people in general don't seem to have a particular craving for celeb gossip. They feel ashamed of themselves, like it's a guilty pleasure, and they wish there were a better alternative. But given their abstract / remote / hypothetical biases, it ends up latching onto celebrities. Who else would better fit their goals here?