Email Marketing

I recently found a form that you could fill out and send to the Joint Advertising Marketing Research Studies Office (JAMRS) that requests that they remove your name personnel info from their military recruitment database and I was wondering if that means that they (JAMRS) have the personnel information of every potential recruit in their database already, or if they pick this info up when you enter college, or if you have to show intrest in joining the military, like fill out forms, and then they log you into the system.

My company is trying to figure out if US soldiers are able to receive email from businesses to their military accounts. I know some emails get filtered out. This would not be spam, but emails they would sign up to receive. Any insight or links on their policies would be helpful. Thanks!
So if I we cannot send to their .mil addresses, do they still have access to a personal email address like yahoo or hotmail that we can send to?