I've been wondering this recently but I figured out I can get something like the below much cheaper, and since there are 4 batteries I can always have two charging whilst using so I'll never need to rely on the cable.
Those charger with batteries seem like a good deal...but the charger is crap. After a few charges, lights will start blinking and the batteries will never charge. I tossed out a few batteries thinking it was the battery when it was the charger. I put the same batteries in my bigger/more expensive charger and they charge just fine.