Casino hosts are known to change jobs (moving to different properties) on a fairly frequent basis. I don't think it is unusual for hosts to keep client databases and take them with them to a new job, therefore, your personal information isn't being "shared" with another property - it is being used by the person who originally obtained it from you, just at a different place. I could be wrong, but I doubt the casinos are paying for lists of this type of information. They are hiring hosts who already have it.