Hi Hank, welcome to the site.
Asking for a picture ID is pretty standard at most of these books. I know 5Dimes asks for it (along with the credit card pics), and I think others have said that BetUS does as well. But, I think this only applies to the wire transfers, so they can verify your identity. It's too bad you can't get a check.
Identity theft is a concern, but I don't think you'll find cases of these books doing that. Could be wrong, though.