They do switch the active charge circuit off but they still waste electricity. For that matter leaving the charger plugged in with an LED light on wastes elect

They do switch the active charge circuit off but they still waste electricity. For that matter leaving the charger plugged in with an LED light on wastes electricity as well, but as the article pointed out the KW per year measurement is so infinitesimally small that you can do more for the environment by skipping a hot shower.