Unfortunately we live in a media rich environment, where people expect a product to have as many 'whistles and flutes' as possible. When you compare the DBMM rulebook against the FOG one you immediately get the impression is has a higher production value, with the inference that it must be a better ruleset. I agree that this is perhaps just an illusion where that ruleset is concerned, but it is non-the-less quite true that a snazzy product captures the audience its aimed at.
I've been wargaming since 1966 and the old school type rulesets a la the old WRG style no longer attract old or new players, who want to have rules that are clear to read, have colour pictures, photo's and diagrams, and at a cheap cost.
I did put forward the suggestion that perhaps on this site we could put up photographs of various examples of play from the rules and then reference this in any new printing of the ruleset, but this fell on stony ground...