They want to make sure they will enjoy the moment – and those that ask me this are told that this is a service and if I have to meet certain qualifications, I think they are in the wrong biz. I am not an ugly man but I don't participate in this. It only means they're going to be half-assed at their job.
Do you tell your chiropractor, barista, store clerk, insert other professional service here, what you look like? HELL NO! They are providing a service. If they ONLY want to see and fuck around with 'pretty people' they should get another job. Otherwise, shut up, take the money and bend over or stick it in (whatever the customer wants).