If you really like charging batteries, you should get into electric aircraft - big monster batteries with high voltage and discharge rates, and they are not exactly safe
Anyway… I know a little bit about batteries and I’m not sure if this is what you’re saying or not, but the capacity posted on the label is not ‘misleading’ if you understand what it really means. It has nothing to do with the self-discharge rate… it only means the battery can deliver that much power over the course of its discharge cycle… which it does. If you weren’t there to use the power when it came out… that’s your problem. NiCad and NiMH cells have fairly high self-discharge rates, so we tend to avoid them on model airplanes because you have to charge them right before you fly, and that is inconvenient, and they are heavier than Lithium-Polymer type batteries. They do have higher discharge rates though, so if someone needs 100 amps or something, they do use NiCad, NiMH or “A123” cells.
We generally use Lithium-Polymer batteries in aircraft, but they need to be handled with care as there is a risk of explosions and fires, so they are not viable as a supermarket-type consumer item. It would be nice if they could be made a little safer though, because they have very low self-discharge rates. I’ll charge mine up and let them sit for months sometimes and they only lose maybe 2-5% of the charge, over the winter for example.