I seem to remember the horseshoe topic coming up once before. Seems like there's a kind of "Glitch," if you will, in which it will duplicate and drop horseshoes and reagents from the first map into the next map if you first walk to said area, instead of taking a boat, horses, or teleporting.The horseshoes you mention near the tavern by Snergle's Caverns would be at approximately the same place on the map grid as they'd appear inside the volcano at New Sorpigal.
So, it may be in your best interest to not collect anything off the ground at first, and instead walk to the next map areas, in an effort to stock up on horseshoes and reagents. (Your party can never have too many phirna roots or widoweeps berries!)
