It is again worth noting that whether counting ammunition is a worthwhile task is a HIGHLY contingent issue. The rules can make it easy, or the rules can make it hard. The rules can also make this sort of thing more or less palatable to players depending on how the rules treat other, similar issues.
In 3e, I hate tracking ammunition for Ranger archers. I rather liked tracking ammunition for my slightly customized shuriken throwing Scout. I sort of resented in general that ammunition had to be tracked when other issues that should be similarly simulationist (or similarly NOT simulationist) were not tracked. So what was the difference?
The archer fired arrows like a machine gun, and his quiver only held 20. He typically ran out of arrows in any protracted fight, unless I carried multiple quivers. But carrying multiple quivers created a contradiction- it was realistic to count arrows, but unrealistic to imagine an archer with three full quivers of arrows on his back. Those are BIG. It became literally impossible to carry sufficient arrows for an extended journey unless 1) I found arrows on enemies, 2) I used magical means to carry more arrows. Finding arrows on enemies was not an option because I didn't want to be at risk of not encountering archers. So I had to carry arrows magically. Once I chose to do THAT, the whole issue evaporated. I got a magical quiver that held lots of arrows. Then I obtained a bag of holding, and stuffed it full of extra arrow quivers. For a relatively trivial cost, I got literally thousands of arrows, and stuffed them in that bag. At this point, counting ammunition became silly. I counted arrows to know how many were in the quiver on my back, and then after each fight I refreshed that quiver. There were two problems with this system, in terms of game play. First, subtracting 15 arrows from my stockpile of 2000 was just annoying. It wasn't like I was ever going to run out. Second, I could refill the entire bag with a 100 gp investment, which at that level, was a joke. Why was I doing all this work to find out if I spent 3 gold pieces at each visit to a town, instead of 4? I made a deal with my DM. I'd pay 10 gp whenever we hit a town, and we'd just stop counting arrows in the bag. I was probably paying for twice as many arrows as I consumed, but I didn't care. It was worth the whopping 5 gp (that's a 100 arrow safety margin) to not have to deal with this anymore.
So what made the Scout's ammunition enjoyable, when the Ranger's was not?
Well, the Scout threw only one shuriken per round, thanks to Skirmish and Shot on the Run. In a prolonged fight, that meant maybe seven shuriken. It was a lot easier to keep track of that. Plus, the shuriken I threw were generally magical after a certain level. This made them more expensive. Unlike spending 1 gp for 20 nonmagical arrows (fired from a magical bow), I was spending lots of GP for Shuriken +3, and so forth. Knowing whether I threw 5 shuriken or 6 was a difference of a meaningful amount of money. Further, I had to carry shuriken of different types to combat different foes. I wasn't counting out 1 arrow from 2000 identical arrows, I was counting out a single Good Cold Iron Shuriken +2 (demon hunting shuriken

) from my supply of five similar shuriken. This made it much more meaningful.
Finally, there was the resentment when I was playing the archer. Why did I have to count arrows, collect arrows after a fight, and generally do all this bookkeeping when the wizard had a never ending supply of bat guano? He never counted that. He never went spelunking to collect it. He never even really BOUGHT bat guano. One day he leveled up, and now he knew Fireball. Suddenly he had all this bat guano. Where did it come from? Nobody knew. How did the bat guano not ruin the other components in the spell component pouch? Was it loose in there? He had a special, non magical pouch that apparently contained every basic spell component for every spell ever written, in infinite quantities. And here I was counting arrows, counting arrows that miss, dividing by two and recovering them, and making sure arrows were wrapped in cloth so they wouldn't pierce my magical bag of holding. This didn't seem fair.
I don't know how all of this will apply to 4e, because I don't know the context in which 4e places characters who use ammunition based attacks. But I hope it illustrates a bit how the game rules can affect the entertainment value of simulationism. Creating a great deal of bookkeeping in order to achieve a very small, easily bypassed outcome is not a good idea. Inflicting bookkeeping on one player and not another, even though they are doing basically the same thing, is not a good idea. Creating simple bookkeeping that has meaningful in game effects IS often a good idea.