I think some people are a little too paranoid. Suppose some random company across the globe somewhere DOES find out your age, D.O.B and where you live. It doesn't mean all of a sudden you are, i don't know, being stalked, likely to be murdered? Email addresses and telephone numbers i agree should not get out, but i don't see what harm can come from finding out details such as your date of birth.
Just my thought on the matter.