Actually, you could even have deadlock: what if simultaneously A made vows to B, B to C, C to D and D to A? Now, for anyone to complete a wedding requires them to be bigamous, but nobody can back out.

True. Of course in the eyes of the church, the wedding isn't binding until it's consummated, either. I am making no comment whatsoever on how that might apply to a A->B->C->D->A scenario. :-p

The hotel might place a surcharge on the honeymoon suite, if only to cover the extra cleaning costs…