“Researchers from Dartmouth College, Princeton University, and the University of Exeter found that around one in four Americans visited a fake news website in the weeks before and after the 2016 election. The study notes that this consumption of fake news was “heavily concentrated among a small group”—almost six in ten visits to fake news websites came from just 10% of Americans, and that those visitors were deeply pro-Trump.”
"The fake news websites were overwhelmingly pro-Trump. Trump supporters were also about three times more likely to visit fake news sites supporting their candidate than Clinton supporters were to visit sites making dubious claims in support of their candidate.
Facebook was a key gateway to fake news, researchers note—something the company initially tried to downplay last year, before pledging to do more to combat it. The study found that Facebook was among the three previous sites visited by users in the prior thirty seconds for 22.1% of the articles from fake news websites. Researchers didn’t find the same pattern for Google, Twitter, or email. “Our results provide the most compelling independent evidence to date that Facebook was a key vector of fake news distribution,” researchers note in the study."
Long story short: it’s primarily old, conversative people who only really know how to use Facebook for most of their online activities with low media literacy rates who absorb fake news.