Hmm? using easy boots to clear up thrush?

my gramma has about 8 horses and they are all outdoor/pasture horses. she has lean-tos for them and a 2 stall barn if anyone gets sick or injured (where my horse is now, shes got a pulled tendon) anyway, the small and big fields get muddy and wet in the winter and stay that way often until spring. we are constantly battling thrush. i wanted to buy that equi-pak stuff but its so expensive. i was wondering if i could bring a horse into the barn, clean, dry and medicate their hooves, couldn't i just use easy boots to protect them and keep them out of the mud? it would be expensive at first, but dont those boots last a long time? it just seemed like a good idea, let me know thanx!