I agree, I do like multiple types of ammo but that is generaly because they can then do other interesting things, like a fire arrow shot from a Sonic Bow causing Arrow/Fire/Sonic damage (yes I did that in one game) but I personally find that many of the food mechanics are overworked and add a level of micromanagement that is a little too far.
I would say Normal ammo is 'unlimited' in that you can just have it, like being fed and watered, but Special arrows are a limited resource that you need to conserve and craft in your Stronghold.
What is the point of using an explosive arrow on a minion, you would just use a normal arrow, but for a horde of minions I can see you using all the explosive arrows that you have. Then it becomes a tactical choice of what you are going to be doing rather than a 'ooo I have flaming arrows'
Just my 0.02 worth