Cycling no, because there are people who are never, ever going to get on a bike -- they simply cannot be forced to.
Yup. There are all kinds of disabilities that make bikes and walking impossible. Many of them are invisible - you can't see if someone has the kind of heart trouble that makes too much exercise dangerous, or if they need a hip replacement.
Bikes are good for some people (like me!), but not everyone is like me.
As far as electricity goes... I'm not entirely sure the average person even knows what sort of power plant provides their electricity. And I'm quite certain that the average enviromentalist is vague on which kinds of electricity generation are cleanest. Protesting against the local nuke plant and proposing a coal plant was fairly common *in Pennsylvania*. It was obvious that most protesters didn't have the faintest notion of what was involved in coal mining, or in coal burning... even tho coal is a major industry in the state.