But, the 'flavour' of exercising BC that has any chance of working is too complicated to ever be sellable.
What is sold (well), therefore, is the 'tricks' approach.
Combined with this: efforts at behavior change, in NL at least, are mostly developed by advertising agencies. They never evaluate; they look at e.g. 'impact' instead. So you're never 'exposed'.
So while using this tiny bit of knowledge we have (which, still, is more than we had fifty years ago) to make the world a better place, we have to keep doing more fundamental research and improving our methods and knowledge translation etc.
We currently know much less than we'd want to - but we learn more every day.
So whatever we do today will suck a lot.
But what we do in five years will be slightly better.
And so on...