They don't have to! Mine found one that had made it's way in through the cellar hatch - and left it's corpse for me to find! (Only one is a mouser).

@RavenCT The mice here tend to stay out in the weeds, or garden/compost area away from the house.

My boy doesn't either, but he knows that there are some mice who sneak into the garage, and he really wants to get one (or more).

@RavenCT Spike has caught some in the house. There's an open field behind us so mousies. The very first one was decapitated, ewww. There was one playing possum. I picked him up and he came back to life. Sadly, now Spike thinks it's great fun and he likes to play with them. Unfortunately they often get away from him and we have a chase around the house. Last year I made a mixture of peppermint oil and water, put it in a spray bottle and sprayed all around the areas where I know they get in. No mice!

@Booklover I will definitely try the peppermint oil and water trick! Fresh smell and less of the mice? I hate seeing the cat get them - particularly if he decides to "play" with them. Ugh. I feel bad for everyone involved.