Kiss, don't take those two look and go guys personally, it's their issue, not yours. Try not to let it bother you.
If face pictures are important to a client, they would be better contacting those escorts who advertise showing their face rather than bothering those who don't. As Amy said, it's boundary pushing, plain and simple. And as Mirror said, and in my experience, as someone who does not show their face, there are plenty of men who will book without seeing face pictures.