Some companies send out surveys to find out what people like or don't like about their products and services. Gallup does surveys to see what people think about various issues. Some researchers conduct surveys to try to determine trends in the thought, belief, or response patterns of certain kinds of human beings.

Lots of campus groups conduct surveys which are worthless from a statistical point of view, and only serve to decrease the total amount of knowledge in the world, and support ill-defined/incorrect conclusions. Some of the "campus faith groups" at my college send out poor schmucks to stand outside all day and ask people to fill out "surveys", which ask the participants if they believe in God/believe the Bible/go to church/etc., as well as ask for their name, address and phone number (for the 'free bike raffle' or some such); then some weeks later, everyone dumb enough to leave their number gets plagued by incessant phone calls asking whether they'd like to come to a church service, or attend a Fun Social Event being held at a church.

The first time I ever took a multiple choice survey, it was the happiest day of my life. For once, I could bubble in two answers for the same question, and not face the consequences of losing points on a test. I'd been longing to do that since the third grade.