Assuming we are talking about the standard hardy white calla, Zantedeschia aethiopica, that IS a large plant and leaves 3-4' tall are pretty standard if growing in good conditions. Actually, your comments are not uncommon - many gardeners find the growth of this plant to be messy or unkempt looking but put up with it for the sake of the flowers.

It is not a plant you typically "prune" except to cut back after frost in areas where it does not remain evergreen. But if you find the foliage excessive, there is nothing to say you can't thin it out some by removing some of the leaf stems just by cutting off at ground level.

btw, despite their common name, callas are not lilies at all but members of the aroid family, like jack in the pulpits or anthuriums.