iOS 7 on my iPhone 5 really did hurt battery life. Then I got a 5s, and battery life was also not great. And then I upgraded to 7.0.3, and things seem MUCH better.
I've used every single iPhone since the original model, about a year per model. My brother then gets my hand-me-down and uses it for another year. I have used every single release of iOS since it came out. So I feel I'm on pretty solid ground when I say the following: Almost every major iOS point-oh release has hurt the battery life of older phones, and it usually takes the second or third update before it goes back to being more "normal" again. So none of this is new, at all.
Also, you have to know how to tweak features that can drain batteries disproportionately. Background app updates? Every single last location service? Automatic app downloads/installs? All sorts of things can be tuned to max battery life.
Finally -- just get a freaking external USB charger already, and be done with it. You can get them as nice cases, or little cylinders from places like nomorerack.com for as cheap as $12, and they make life on the road as a modern smartphone user MUCH MUCH better. As in, you'll wonder why the hell you didn't get a stupid little $12 USB charger much earlier. I have a small one, and a larger one, and they are life savers. I don't mind carrying one around at all, they weigh almost nothing.