Theme an preference

I myself feel kind of neutral about the theme of a game. I want it to work with the game but I am more interested in the gameplay than the theme.

Just out of curiosity, what do you guy feel makes a theme attractive to players. I am not looking for individual elements like zombies. Instead I am looking for something like humor.

I know what types of themes I like.

Also I am just curious and not going to use this for the design of a game or at least I an not planning to.