All of those are only zero-sum if you pick a conserved metric. Land ownership is zero-sum if measured in square meters. But say someone buys up land that is parched, dead, and empty. They use it by planting moisture-retaining crops and windbreaks and growing food, or running a business of benefit to the community. Now overall everyone is a little better off, despite 0 square meters being created.

Influence is even more so -- it's common to have situations where nobody is truly paying attention to anyone else. The people with good ideas can't get any traction, and the whole organization just spins in circles, lurching from one externally-imposed crisis to the next. If the people who gain influence use that influence to promote others who are worth paying attention to (and thus they gain influence), everyone benefits. But if you measure that in terms of how many minutes each person gets to speak at the All Hands, it's zero-sum.

Yes, but in practice land-ownership is only zero sum in places like Europe where every square-kilometer has 300 years of documented ownership etc, or other high-density areas.

The Asia, Africa & the Americas have so much unused space that isn't as inhospitable as central Australia

Most games are either negative-sum or positive-sum. Very few are zero-sum.

I feel a strong impulse to conserve all of your matter towards the inside of a locker.