Interesting, I think you have to consider the system as a whole and the impacted stakeholders when considering pricing.

In your example, if we consider the environment a stakeholder, and the fact that increased safari impact has a negative impact on the ecosystem, there's a stronger argument for higher price.

In the case of the Louvre, the paintings and sculptures aren't going to be harmed by having more eyeballs on them, so, there's a stronger case to maximize access.