Spitting, liturgically, has a secure and respected place in the Traditional Roman Rite. The collect for the Third Sunday AFTER Easter is thought to have emerged from a context in which the Roman Pontiff was campaigning against pagan survivals, particularly, perhaps, the Lupercalia (February 15) celebrations; so we pray that all those whose names are on the Official Christian List [Christiana professione censentur] may "spit back upon" [respuere] everything which is inimical to that Name. (I think the collect survives in the Forma Mutila et valde Deterior of the Missal, on Sunday XIV per annum.)
And there is First Millennium evidence that the Pope, when proceding through the City, was preceded by a minister carrying a spittoon to receive the papal ejections.
Good rich wholesome traddy stuff.
And I noticed the other day a Tudor example. It was a great day ... 1553, June 1 ... when Anne Bullen (Boleyn) went to her coronation. She had set off from the Tower of London days before "Apparelled in riche clothe of golde, [she] entered into her barge ... the bachelors' barge going on to the Queeene's right hand, which shee took great pleasure to beholde": quite probably ... perhaps one of those admiring bachelors was her own favourite (perhaps very favourite?) brother ...
Days later she sat, crowned, in Westminster Hall "under her clothe of estate ... on her left hande stoode the countesse of Worcester all the dinner season, which divers times in the dinner time did hold a fine clothe before the queene's face when she list to spit, or do otherwise at her pleasure ..."
Ah, those days of 'otherwise' pleasures and of limitless listing ...
I don't know how common this good old custom still is today. In S John Henry Newman's day, the future Archbishop Whately still kept up, in the Oriel Common Room, the habit of spitting into the fire.
I think the tradition is now confined to Association Footballers, whether or not they are in Oxford Common Rooms. Do our Oratorians ... er ...
From my childhood I recall that public conveniences for the use of males once had notices designed to be read as officiants prepared to walk out: COMMIT NO NUISANCE.
Y'know, I never did.