Why do people ask questions that no one can really answer?

Like questions where they give examples of things and want to know if they like them. I mean...we can't realistically say yes or no because we know nothing about the other person. For all we know, they are like that with every person. It just boggles me I guess and I don't understand. Isn't it more harmful to yourself to do that? Cause it gets your hopes up so high based on stranger's opinions?