Social Security, dark web crackers, and crappy online forgotten passwords websites want to know your location. I jest. But seriously, DOB is extremely valuable, which is why I never use my real one online except for government stuff like that.
To the poster it sounded like he didn't want to hand that info over. I don't know the reason, I was just providing a fairly simple solution.
Also dob is frequently used as a verification. So it is kind of a big deal.
Maybe that's the point. It's not a very secure method of verification, so it is sensible to want something better, like an ad hoc secret phrase.