I've always tended to land a foot/18" left of the centreline and even in a flight sim with a TRE from a major airline observing, I did the same repeatedly and he couldn't see any tangible reason for it , just saying it wasn't dangerous and it was consistent (they lilke consistency.)
I thought it was just me!
NB that on Barra (Scottish islands) there is a scheduled service which lands on the (licensed) beach airstrip. The AIP entry makes interesting reading.
Tim