Dear paranoid,
a displayed 'fake' number is only one part of the safety issue, as the sp should also, if she doesn't 'recognize' the number, call the client back at the number displayed. I don't believe the technology allows you to post a fake number that will then route calls ... it would just give a message saying that number does not exist.
and the safety issue goes both ways ... one reason i have almost 100% of my sessions with the agencies is that i know what i am walking into most times.
with the indies (though they have been great!) who knows what could have been behind the door? and that doesn't mean just the sp herself, but one of the many stalkers out there who we all remember used to hang out here ...
so while i do agree with your concerns, i cannot agree with your approach though ... if you don't like something that has been posted, politely ask that it be removed -- many of the posters are reasonable about it.