I think another really important thing to remember is, there are many providers (probably more than you think), who have civie jobs, or an s.o. with a good income. So, the hobby $$ is just supplemental. So, with me, if I can't verify someone and have to decline an appt, it's not a devastating financial blow.
As others have said......I find the majority of men are more comfortable with a girl that screens. BP girls that will see you last minute with no screening? Streetwalkers? Doesn't that scare you? This is the manner that l.e. stings are operated for heaven's sake.
I do feel for the newbie that is sincere about entering the hobby. There are many newbie friendly girls out there. And, I am still perplexed at how many men are still fearful of p411. It's reputation speaks for itself.