i did not look into this until recently. there was a big post announcing this feature to reduce bullying.
i do think that paying 100 honor for players on their ground might work for the early game, but once you reach lvl 30+ it just feels like a joke.
you get 1-3k honor for a field battle and most players can make 5-10k honor a day.
which means they could attack 50-100 players a day, assuming they would get 0 honor for all duels.
i think to make this feature work, the amount you need to pay has to scale.
at level 30+ i suggest 500 to 1k honor to make players even think about not doing it.