Because I often fly in the USA ... at a "towerless" field, with a common traffic frequency on which I and the others make "blind calls" then all of the possible consequences of the things outlined by possibleconsequences are out there waiting for me.
But because I am following the "relevant proceedure" which is (effectively) see and be seen, then they are part of the risk and are accepted and I have to be that bit more vigilant and aware.
However .. If I was at a controlled airfield and for whatever reason did not get landing clearance I would not land - simple as that.
I am really surprised this thread has lasted so long.