Do you recieve emailed surveys?

Two of them arrived in my mailbox this morning. One from Winzip and another on Lifestyle. After starting it I found some of the questions were designed to find out how much I was willing to buy from them now or in future. Do you make your purchasing decisions based on that? Much of the time I don't decide to get anything until there is a clear need for it. In that case I search for the most suitable thing to meet that need, whether it is software or other stuff. How do you react if companies ask questions about how much you plan to buy from them?