I see them as poor's man touring bike. Actually, I find MTB more adequate than many "touring bikes". Better gearing in most cases, stronger 26" wheels, no concern with large tires. The only downside is the suspension fork and in some case, the shorter chainstays. Then even some touring bikes have rather short chainstays. Rigid forks are rarer, but you can always change it. If I had the knowledge I have now when I bought my bike, I would've passed the tourers and looked at MTB first (my bike is fine, just want 26" wheels).