There likely was a lot of bodged bikes that did tours before the Surly era. Now? I doubt there's 2% now on CGOAB.
Most were bought new for the purpose. Still some broke spokes the first week. LOL.
And yah, I know many riding these new bikes brag about $15 flea bag hotels in Asia. NOT me. LOL.
I've done lots of century rides on my heavy tour bike with both the Rohloff and SA 5w.