I don't necessarily think the point of asking someone's age and name is an invasion of privacy or being overly selective. Most clients are willing to offer that information anyway. With today's text and email as forms of contact before meeting, it would be careless not to.
I personally have come to ask everyone their name, age, and sometimes even stats/ethnicity before meeting IF...they contact by text or email. I rarely ever have anyone turn away because of that. Asking for a picture, yes that's a bit over the top. But...more than enough people voluntarily send me their pictures anyway, and have become real actual clients. Especially with adam4adam, I don't even have to ask...and in fact I stopped meeting adam4adam clients who don't have a picture. Usually not serious is why. Most do, There's never been a reason to...unless they contacted me prior from another site, with that information.
It's just common sense. Instead of a text ban, I've been able to compromise. I don't ask as a means of sizing someone up, but it can make the difference between a legit appointment, and something a little more sinister.
Asking these questions can save a lot of headache, especially when traveling. I once neglected to ask said questions, and ended up driving 30 miles in LA traffic going to a home with an under aged looking Asian kid who seemed a bit mental. Had I asked, I'd of spared myself many hours of wasted time. I also have a persistent stalker who contacts me every few weeks from different numbers trying to book me, and those verifying questions help me quickly stop him in his tracks.
Everyone has their reasons, but for me it's for verification purposes. Nothing personal.