I appreciated the fact that when I ran out of ammo I had to resort to other means of combat w/ the characters that typically relied on ranged. I find it WAY more relative to the important aspects of the game than food, for instance. It makes you have to plan in advance and modify your behavior if you haven't or weren't able to find an adequate supply. Missiles take up inventory slots so that's another factor to have to consider and I say fairly negates the "well I'll just buy a years worth" argument.
Planning, strategy, and combat are what I enjoy about these types of games. Unlimited supply of ranged weapons isn't useless minutae. For the record I would be completely OK with having to repair armor etc given that there were adequate means and methods. There certainly are a number of anvils and workbenches in the first part of the game. Throw in some NPC's here and there that can perform repairs and bingo bango there ya go. I would MUCH rather have this than the food which has already been discussed. It also adds an element of potentially improving items beyond their standard stats by either combining with other items or having an NPC vendor do it for you.
