Sleeper trains make so much sense for travel over land. They are often competitively priced with air travel, they pollute a lot less and the time saved can be huge when you consider that you spend time travelling when you would otherwise be asleep (although this is sometimes true for air travel, many/most people find it difficult to get quality sleep in economy class). The London - Edinburgh sleeper train (Caledonian…
Problem is they really don't quite make as much sense for city pairings that don't fall into the narrow window of roughly one night of travel time. This severely limits the amount of mainstream awareness sleeper trains can reach, so people who don't routinely travel such a route won't have them on their radar when they do.
You can see the Caledonian Sleeper timetable at [1], it's also reasonable to catch it at Watford. It then stops at both Edinburgh and Glasgow (they have split the train in two further south). You can see the Highland train stops at many towns and villages.
You do need to be a bit more alert if you're getting off the train before the terminus, but the attendant will almost always wake the passengers who are due to alight.