They are phishing for information, not necessarily personal information, but usage information.
Have you bought a turtle may refer to owning exotic pets.
Were you born in [random month] may refer to the Zodiac Calendar or wanting to know how many people were born in that month for a census project.
Did you use your oven yesterday may be a selling point for an appliance company.
Surveys are conducted by companies who do nothing but conduct surveys. They are hired by large companies to get a idea of what the general populace is interested in, behaviors, marketing advantageous and the like. They are asking the same questions of thousands of people who voluntarily answer surveys, like you must have done.
Before computers became a household item, people who worked for survey companies were frequently found in large malls. They would stand in the middle of the crowd of people walking back and forth asking, "Would you like to take a survey?" If you answered, yes, they would take you into a room to either fill out a survey or they would ask you questions about your usage of certain products. Some paid you money to take the survey, usually $10.00 or $15.00. When word got around, people would ask how much they paid for doing the survey. If it was less than $15.00, then most would refuse.
When I was short of pocket money, I'd go around to the different malls and answer surveys. In an afternoon, you could make $60.00, but you couldn't go back to the same survey company.
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