International League Legends of Heroes

As I understand it, "advanced" Heroes of Might and Magic players are actively using the WBN ladder in games... but are their opponents using it too? Because, as I recently heard from one player, when asked if he uses the ladder in SOD, he said "yes," and when asked if his opponents always use the ladder, the answer was "I don't know." I understand that opinions on this can vary, from, for example, "I always offer my opponent to play with the ladder" to "that's the opponent's problem," or simply "what, does anyone still play without it?" I'm not sure how things are in this tournament with international players... But if one person uses it and the other doesn't, IMHO, it seems a bit unfair.