This reminds me of the discussion of earlier this year concerning where do Churches come up with things like: " at
St. Bernard's". St. Bernard is dead, cannot be a possessive.
Yet even at the Vatican it is St. Peter's Basilica, in London it is St. Paul's. Someone mentioned the 'genitive' case above: which
as I understand it, indicates 'possession', yet a dead saint cannot possess a Church, etc.etc.etc. I like Pook's comment: don't expect consistence in the English language.

----please, draw me a sheep----