In a DoD environment I Tunes, Amazon Downloader, and other legal forms of downloading music are prohibited from being on the systems as being outside the baseline. I can only speak for the Army but the regulation does not consider music in general stealing. Quoting from AR 25-2 page 27...
(7) Certain activities are never authorized on Army networks. AUPs will include the following minimums as
prohibited. These activities include any personal use of Government resources involving: pornography or obscene
material (adult or child); copyright infringement (such as the sharing of copyright material by means of peer-to-peer
software); gambling; the transmission of chain letters; unofficial advertising, soliciting, or selling except on authorized
bulletin boards established for such use; or the violation of any statute or regulation.
In short DISA wrote bad flash training on this one scenario. DoD 8500 series and agency specific regulations DO NOT refer to it as stealing.