> There are HOAs where people get fined/punished because a package was left on their doorstep for too long without being picked up. I'm pretty sure that has nothing to do with property value.

It does, indirectly. It is perceived that a pattern of packages being left outside attracts thieves to the neighborhood, increasing neighborhood crime rate, decreasing property values.

(That's not to say that individual HOA actions in this area are reasonable or proportional, just that there is a nexus with property values.)