The answer comes from the lack of time to answer a survey or a lack of means to do so.
After reading a long text or let us say, going through a long process, or watching a movie, most people don't have either the time, the means or the desire to write down their exact feelings for what they have just experienced, or have experienced in the past.
It is just a process to speed things up, a little like when you ask someone "How are you doing?" and he answers "Good, I'm doing fine." It a generality to sum up what he has been experiencing.