They can be a pain the arse but they do help make nice soil too. If you want to get rid of them partially boil some rice and either put them or other chitin rich insects like mealworms out in a box in a natural environment like a woodland and hopefully you will capture some chintinase producing bacteria to break them down in to plant food. Mix this inoculated rice up in some unfiltered water pour on the area and hopefully the bacteria will turn all the munching critters into plant food for you.