That is a good point. I guess a better way of saying it is that I assume (or hope) most people are behaving mostly well most of the time and at least in the short term interest of most people.
This is also an assumption that is a luxury due to me living and growing up in a stable and prosperous country, and I can certainly see different circumstances producing different mindsets.
But I also think there is plenty of good being done by organizations (at least the ones I’m familiar with in the US) to justify giving them some benefit of the doubt.