Yes, having wheel lights means more things to fuss with and more things to charge. My wheel lights though ( two on each wheel ) are small and use only one AAA cell for each. In all I have to routinely charge via USB 11 different things ( each wheel light I count as one ), not including my phone or the lamp that uses an external battery. Yep, that's a lot of stuff. That's why I just bought a ten port USB charger as I was running out of USB charging options.

While you really don't need something like wheel lights they are just so cool that having them makes it worth the added chore of charging the batteries. I get compliments on them all the time. Nothing makes a bike stand out at night from the sides like good wheel lights. Just the other night I was riding along and passed one of those glass enclosed bus stops. As I did I just happened to turn my head to notice that the glass was acting like a mirror and I could see myself riding by. This is the first time I ever actually seen what my wheel lights look like from the observer's POV when riding at night. Absolutely awesome!