A couple of years ago I built a vermicillain (worm) compost bin. It was working real well till the firants moved in. However, I thought about it and left them alone. I continued to feed the pile with kitchen scraps. The ants killed out all the worms, but began to eat the scraps and turn them into nice usable compost. Never thought I would be glad to see fire ants but me and these guys worked together all summer till the cold weather drove them back to lower ground.

Normally I would agree that the presence of ants in a compost pile is part of the normal process. HOWEVER, fire ants are a non-native invasive insect species which should be eliminated. They are crowding out native species of ants and as you already noticed, other insects which inhabit the compost pile. Somehow I doubt that their droppings are as good as worm castings and their sting is very painful.

Glad the fire ants "worked" for you, but having been stung by them while sifting compost yesterday, I'd recommend trying to keep your worm bin moister to discourage ants.

Probably what the native Americans said about us.