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Hot Tabasco said: "... a severe scolding."

How about a scolding for the park service?

The man who knocked down the rock did so by being able to put kinetic energy into the rock in synchronism with the movement of the rock.

At the full extent of each movement of the rock, the kinetic energy is transformed into potential energy at the point where the rock stops moving.

The rock then reverses direction as the potential energy is converted back to kinetic energy and the rock moves back toward the man. At some point near where the rock was found initially, the kinetic energy would be at a maximum.

The rock will move past this point of maximum motion, converting kinetic energy back into potential energy, until the rock moves sufficiently toward the man to convert all the movement into potential energy.

Now here's where things get interesting. There is no guarantee and practically no possibility that the amount of potential energy needed to permanently dislodge the rock is the same in both directions.

The man pushing the rock faced perhaps an equal chance that the rock would dislodge itself toward him rather than away from him.

Is every visitor to the park expected to know this? I doubt it. Would the park service personnel be expected to know this? I think so.

If the park does not contain signs such as:
Enter At Your Own Risk
No Unsupervised Minors Allowed
Stay on the Marked Trail
Do Not Touch the Rocks
Caution: Dangerously Unstable Rocks - Stay Away

then perhaps we need to consider jailing the government agents for having created an attractive nuisance and for having endangered the lives of those who have visited the park.

I think the man who dislodged the rock won a lottery which he could just as easily have lost.