Everyone "should be", but the reality is that everyone isn't. A fairly small proportion of us have the time, energy and motivation to research the best decision for any given situation.

So it is totally reasonably to argue for making the right choice the obvious one, e.g. by externalising the costs of bad choices. It doesn't help until there's a majority for it, as you point out, but one way to build public support is to build awareness and criticise the current situation.