The unspoken assumption behind this is that atheists aren't human. Though, having said all that, their findings do disprove this obvious nonsense.
Most religious folks are conditioned to distrust anyone who is not part of their flock. Atheists often get more of the brunt of the dislike, but it permeates to any faith that is not conducive to the status quo of that particular religious branch. Most Catholics distrust Protestants. Most Protestants distrust Mormons. Most Christians distrust Muslims and vice versa. All religions have to paint anyone outside of their faith circle as being 'the other' in order to reinforce the notion of staying with their particular brand of religion.
Back to the Kent study, it somewhat reminds me of that Pew research poll conducted a few years ago that tested religious knowledge. And to the surprise of many, atheists scored the highest. Which debunked the notion that atheists weren't well informed about religion. It actually proved they were the most well informed.