I very much doubt they will be doing "menial" type jobs, though, more likely lower end professional roles. The type of weekly commuting being referred to above does go on in China, the poster concerned being rather biased that way in his experiences.
I bet the number of people weekly commuting to work on the tills in Tesco in the UK, or to clean offices, is somewhere around or actually 0. That sort of commuting does happen in China from the rural areas where there is often little work. But that is due to the nature of China - rural nothingness with a few massive cities - versus the UK where you have a much larger number of smaller towns and cities providing work, and no real wilderness unless you go to the Scottish Highlands.
I know one and he flies (Sleasy from Luton), but one is obviously only anecdotal. I do however believe you are right, and it is one of the reasons the Aberdeen is increasingly a basket case - how things change - I can see it being dropped at some point as just having the Highlander do Inverness and Fort William would massively simplify the operation, and if they would tweak the timings slightly so the connection wasn't just 4 minutes then you could connect via Edinburgh off the Lowlander to Aberdeen and arrive by 10am, good enough for most purposes.