Your choices are already being shaped in that way. That's why, for example, modern residential roads are designed with shorter sight distances, narrower lanes, speed bumps/humps, and more roadside shrubbery compared to their counterparts from a century ago. It turns out that the mere suggestion of a speed limit—albeit carrying force of law—does not make everyone choose to drive that speed. Instead, human factors are taken into account so that it "feels more natural" to drive the road at the speed the engineers intended. We try to make it easier to use the system in a way that is safe and accomplishes the user's goals than in a way that causes harm.
Human factors isn't a binary question of whether or not we influence the choices made by individuals. In the real world, individual choices are always influenced by a variety of factors. The question is that, when we are aware that a particular design decision will influence the choices of individuals, is it ethical to make that decision in whatever way maximizes the profitability of the product, without regard for any predictable impact it will have? Simply maintaining willful ignorance of human factors in engineering does not make the world functionally better or worse than if that same decision had been made from a position of understanding of those factors and an attitude of malice/benevolence/apathy.
I don't think it's contradictory to tell consumers to make their own choices while at the same time telling producers not to design products that needlessly influence consumers to make destructive choices.
