When we lived in a town we always kept our cats in at night - provided they would come when called! I had to imitate the squeak of the fridge door opening to get one of them to come.
Even after moving to the countryside, we tried to get them in at night. Now, though, one of them is 'adopted' - well, she adopted us - and has been accustomed from kittenhood to being able to go out at will. So the cat flap remains unlocked.
However, both cats stay in more often than not, or only stay out for a while. Mostly the adopted one sleeps, like a ton weight, on our bed. That is, when she's not bringing in live mice/voles/shrews for us to catch in the middle of the night, resulting in me trekking to the bottom of the drive, to put them on the drystone wall, wearing only my nightie .
They will both use a litter tray if they have to (snow or heavy rain) but I suspect they prefer the churchyard!