Sleeping. It is commonly known as a quiet activity, a way to recharge for the next day. There are those who are silent sleepers, those who are light sleepers...and then there are those who are loud sleepers. Their noises keep other characters up and cause them to suffer from Sleep Deprivation, leaving them cranky the next day while the noisy character feels fully rested. This is quite prevalent in fiction, but in Real Life, snoring in particular can leave the snorer fatigued as well as the people who are disturbed by it.
Taken to extremes, a character who makes a lot of noise when they sleep could catch the attention of other characters who live outside of the main setting and invoke a Distant Reaction Shot. Loud sleepers may also drool in their sleep.
A specific instance of Misophonia Gag. If the trope is exploited, it's a case of Torment by Annoyance. Sleepyheads are prone to doing this often, as are Heavy Sleepers. Can very easily result in someone being Exiled to the Couch, either the snorer or the sleep-deprived bed partner, depending on personalities and circumstances.
Compare Catching Some Z's, when characters have "Z's" fly out of their mouths while snoring that may affect other characters, Snot Bubble, the anime version of the former trope, and Talking in Your Sleep, which might overlap with this trope.
This is Truth in Television, as loud snoring is very common in Real Life. As such, No Real Life Examples, Please!.