Years ago I was a big proponent of "make sure none get away!" Now I've realized that when an enemy "leaves," it's 99% the same as killing them. Unless you / your DM wants to make a point about enemies coming back to attack again (or they're some kind of named / reoccurring villain or whatever), there is really no good dramatic reason for them to do so. All you're really doing is wasting player time with something that isn't surprising or interesting. Same line of reasoning that many enemies will flee when they're suddenly outnumbered and many of their comrades are dead - because in reality, the last few rounds of mopping up aren't really dramatic or interesting from a story-telling point of view. And when your game time is precious, skipping anything that isn't the meat is paramount.
So another way to look at this is: turn undead is awesome, because you just defeated all those monsters. And you are winning much faster than killing them with damage. Just because something doesn't fall down with your sword in its head doesn't mean it isn't defeated. From this perspective, the limits on turn undead make sense. And while it's a cool power, it's still pretty reasonable and restricted (so limited in application).
But if it still bothers you, you can always do what I used to do because it bothered me: houserule that anything turned is destroyed completely. It's virtually the same; you're just changing the flavor to speed up the game in a reasonable way. (And now you can pick up the worthless bow that skeleton was carrying, yay!)