When you talk about overnight camping touring, what are the surfaces you'll be biking over? Will there be unpaved trails/tracks as well as paved?

For road use in overnight trips, the durability issues are less important. If you want to get a Surly LHT, go for it! Even if you don't like touring, you can still use that bike for just about anything else, like getting groceries, commuting, or just cruising around the area. Though you'll probably want to set up the Huffy for any activity where you leave your bike in public unattended, so you'll lose less if it's stolen.

That is the department store bike's one shining good point. It's an "I don't care what happens to this cheap thing" bike, that you can put in situations where you'd never dare to risk your nice shiny wunderbike, like winter riding and general errand running tasks where you have to park your bike for more than 60 seconds.