As a pro-domme I would rather be concerned with a client who easily hands out his Id. If the customer doesn't care for his identity, what else is he not caring for.

And vise-versa: I am not a suspicious person and it makes me uncomfortable if a person who I am dealing with is suspicious. This applies to private life as well as to business. If people don't trust me, why should I trust them?
That doesn't mean not to apply some common-sense precaution.

But I just don't deal with people who are too suspicious.