The users were low-ranking US military service members. In that context, "grunt" does not particularly have any negative connotations, and if these folks were

The users were low-ranking US military service members. In that context, "grunt" does not particularly have any negative connotations, and if these folks were in reality REMFs, could actually be considered a compliment. Military slang is a whole wonderful world of its own http://www.urbandictionary.com/define.php?term=grunt http://www.urbandictionary.com/define.php?term=grunt