I think, part of the issue is that, as a mass of humans, we tend to be rather dumb. And they certainly don't decide on merits, in aggregate. It is somewhat questionable if they decide on merits even as individuals ( unless we expand the definition somewhat ). But it is possible I got too cynical.
It's a paradox: on the one hand, if we were dumb en masse, it's hard to see how we could have developed so far technologically and cultivated such complex societies.
On the other: I have to agree with you, there is too much of a pattern of bewildering behaviour not to.
I think what irks me is this idea that deceiving people to push them towards a specific outcome is a reliable and sound strategy, when we've seen many instances of it having the opposite effect.