I admit I'm one of the paranoid ones. To me it has little to do with trust, really. If/when I'm with a companion I trust, I'll gladly share my personal information. However, I simply don't want my "real" information connected to anything electronic, if I can help it. To me there just seem to be too many scenarios in which something negative could happen, and I don't mean only malicious. So, I'll gladly share pretty much anything a provider wants to know in person, but online I try to hold on to my anonymity.
By the way, the way I understand the law, companions at this point in time are working legally, but clients are still committing illegal acts. (Bizarre, isn't is?!?) I realize that may be a technicality, and is extremely unlikely to be a problem with well-known providers, but why take the chance? I'm also aware that my anonymity is likely an illusion, but... I'll take the easy steps I can.
Just my 2¢. Take it for what it's worth. (And I don't think it's even worth adjusting for inflation.

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