There's no way asking a client to send a face pic has anything to do with their security. They have the discretion, at any point in the setup, to cut something off if they don't feel secure. Having the photo of the person standing at their door waiting to be let in for the appointment doesn't increase security. And for clients who are being discreet, sending a face pic, with technology that is available on the internet, is abandoning discretion.
For every provider who thinks he's hot enough to dictate the terms, there are a dozen who are much better at giving the intimacy and comfort I'm looking for without the added complications.