People don't make sense. It's entirely possible for people to having logically conflicting assumptions without realizing those assumptions conflict. How people respond to questions is also influenced by how the question is asked, and even the order the questions are asked. Making good surveys are hard for that reason, as once you recognize logically inconsistent trends, you have to figure out if the result is due to the survey itself, or you truly revealed a quirk about how people think about the topic.