First, I don’t have an answer, but I’m commenting because I was reminded of a recent experience I had.
Last week, I turned down a job offer, and it was largely influenced by the information the hiring agency, which the company went through, required me to provide. They wanted all kinds of information about me, and it was clear it was almost entirely unrelated to the company offering me the job. They simply wanted to add me to their line of products, whether I wanted them to advertise me or not. If I didn’t provide the information, I didn’t get processed.
Needless to say, I’m happily looking for employment elsewhere. I firmly believe this is both wrong, and a practice which should be illegal. If it isn’t already?