Overpriced Re-naming of items in anvil

When re-naming an item with multiple enchantments in an anvil e.g (sword, pickaxe), the item takes the amount of experience points to re-name as if you were adding another enchantment to the item, even if you are only re-naming it. For example a sword with 3 enchantments on it would take 8 levels to re-name, even if you are adding no additional enchantments.