I don't know if this is that interesting or not, but it's something I've thought about a few times: shows where the piece of music used for the closing theme is heard only for the closing credits and nowhere else in the show.
Shows like Match Game 7x don't qualify, because they play the main theme going in and out of commercial breaks, and when someone wins the big money. Treasure Hunt doesn't qualify, because in some of the episodes circulating, they play the main theme win someone wins a big jackpot. The original Family Feud doesn't qualify, because they played a brief snippet of the theme when the host enters, and a longer edit when a family wins the big money. Hollywood Squares in the '70s played the theme when describing secret square prizes.
This is what I've come up with:
All-Star Anything Goes - vocal theme played only at the end of the show
Bullseye
Dating Game - ABC starting in late 1972 until the end in July 1973
Dating Game - 1978-80 syndicated seasons
Dating Game - 1986-87 syndicated season
Joker's Wild - 1978-86 syndicated seasons
Whew!
If anyone finds any that I've missed, feel free to add if you want.