PragmaticJen - it's simple. The seller uses a non-related third party as an intermediary for the payment. The trail then stops at the third party (or even more, depending on how nervous the seller is of being picked up). Simple bank transfers are not the way ahead for the secret-selling member of HM Armed Forces!
Not good, and the NOTW needs a rocket up it's arse for "not wanting to hide the truth". When the Sun editor got caught out slapping her husband (Ross Kemp), ARSSE went on the warpath, and the Sun simply ignored the backlash. The Services are an easy target, and before much longer I suspect we will get our fair share of journos coming on here touting for stories and information.