In the wild it makes sense to have a hoof preference, because in emergencies, one side of the body will take the lead.
Do the test:
Step 1: Place some food about 5m in front of your horse.
Step 2: Encourage it to come forward and eat the food.
Step 3: When it begins to eat the food, note whether the left or right hoof is placed furthest forward.
Step 4: Do this twice more.