It seems built into human character to bite off far more than we can chew, as in free real estate, and then leverage the social value of holding something others are willing to compete for. I think it amounts to a social survival instinct, and i lament how there's very little chance of discouraging people from doing it because of the potential payoff. If anything i think it's a failure of institutions for being built to exploit that competition rather than guard against its excesses.
People who view themself as rational / technical might be even more prone to not realizing how much they are affected by this? If your self-image is that you are very rational person (more rational than others), you might be especially prone to denying and therefore not being aware of biases.