We are at the mercy of the landowners

It is a mistake to deny access to resources to other people if you do not need the resources yourself. This is not sharing your assets, because you can still retain their use, when you need them, but making excess resources available when you can. To charge rent for these resources is exploitative since we know that you do not need the resources for yourself so then you are profiteering at the expense of others. If we do not make our resources available, we might call this sharing resources, then we have missed out on the opportunity to assist other people.

If we have resources, we have an opportunity to help others. To charge (excessive) rent is to miss out on the chance to help others by providing your assets at no charge. If land (or the air we breathe) is owned by others we are at their mercy to survive. We are craven to the landowners if we wish to survive.