Your argument boils down to "Calculating expected utilities is hard, therefore its rarely worth trying." I agree with the premise, but the conclusion goes too far.

There are many situations in which I have done better by considering possible outcomes, the associated likelihoods, and payoffs. I have used this reasoning in my (short) career, in decisions about investing/insurance, in my relationships, and in considering what charities are worthwhile.

Yes, in many situations good habits and heuristics are more useful than thinking about probabilities, but you get mighty close to reifying our "intuitive decision procedure" aka our stone-age brain which was programmed to maximize inclusive fitness (which does not weigh heavily in my utility function) in an environment which was very different from the one in which we now find ourselves.