From the first article:
Verification
Once your Escort has answered your initial email or called you. Now comes the verification phase. I don't mean your driver's license I mean escort references. If you've never seen an escort and have no references, then the escort you are trying to book is going ask for information that will appease her concerns that you are not some police officer or other government agency trying to entrap her. She will also want to make sure you do not have a bad reputation for ripping off or abusing escorts.
Therefore the escort is going to ask for what seems like personal information, work phone, company name. Don't fight it. She's merely trying to protect herself and her clients (perhaps soon to be you) from potential problems. Keep in mind she wants to make the appointment too and has a vested interest in "discretion." Some escorts ask for a little information, some ask for more. If you refuse to provide her with the information you can forget about an appointment with the lady. The Verification is a safety process you normally can't negotiate. Either you meet her terms and respect her wishes or she will choose not to see you.
In case any actual newbies see this thread and read that article there's something that should be mentioned.
That is written from the provider perspective and yes some ladies will ask for personal information. They are certainly entitled to do that and can do whatever makes them feel comfortable. I would never begrudge a provider from having that right and what she does for her own safety.
With that said, from the client side, if you care about your privacy and anonymity FIND ANOTHER WAY. See a girl who will not require you to do what she will certainly be unwilling to do, i.e. reveal her own personal info to you. These girls are out there, find one of them even if it means being flexible with the selection. Consider it an investment in your hobbying future and peace of mind.
Once you sacrifice your anonymity you have no way of knowing what will be done with that information both now and in the future. 95%+ of the time you're dealing with a perfectly sane and concientious provider who would never do anything untoward with that info or share it with anyone. However, some of the time they're batshit crazy or vindictive or unstable or just plain indiscreet and will share that info for any number of reasons large and small.
The problem is that from a distance you can't tell which is which...until it's too late. Lives have been ruined. Believe it. Ask any long time hobbyist and they'll tell you the same. Hell, ask any long time provider about horror stories involving either provider or client personal info being later used maliciously or indiscreetly.
Everyone should protect themselves, client and provider alike. Anonymity is a part of that.