The very best way to deter church shoppers and potential new members is to list sermon titles, topics, and the speaker in the church newsletter or on the church website. (Special occasions an exception.)
Potential visitors often check out church websites. If they like what they see, they're inclined to visit. This desire to visit may be thwarted by a particular sermon topic. For current members, listing titles creates a "pick and choose" faith, i.e., I like that sermon topic so I'll be there; I don't like that sermon topic so I'll stay home.
Listing sermon titles is a lose-lose situation all around.