Well, this thread turned out to be interesting.
I agree that most of the utility of a element of gear is achieved by buying the basics. Fitness for use product liability laws make sure of that. And if cheap also means light and the item doesn't leave you stranded, you have avoided carrying weight now that will be utilized only on future trips. And I also agree that if you don't abuse equipment even cheap stuff will probably last longer than the buyer (except tires IMHO).
But unless you choose to be wilfully ignorant (a legal term not intended as an insult) what you don't get with low end choices is peace of mind, fit, and optimization. With cheap stuff you must tailor your needs to your equipment, not the other way around. And for many people that is frustrating. If we are talking about bike fit it's downright painful.
As a hobby, bicycle touring is not expensive compared to others. When not touring, the equipment has other uses and can be loaned to family and friends. Touring takes up lots of time, but the variable costs of shelter (if camping) and eating (if buying ingredients from grocery stores) are very low (free if stealth camping or dumpster diving -ugh!). Buying even the most expensive bicycle touring equipment is cheaper than buying a boat or RV, for example.
But I wonder if the cheaper-is-best aficionados know what it is like to ride a custom fit touring bike with the best components or camp with a high end tent and down bag or cook on a stove that uses unleaded gas. The Thermarest NeoAir is currently the highest price sleeping pad on the planet (also the lightest), so even those who advocate cheap really don't mean cheap. We're only discussing where the expense / comfort line is drawn. To me, if my gear keeps me out of a motel for one night, that's (including eating dinner in a restaurant) $50-70 dollars saved. Ten nights saved is (almost) a Hilleberg Allak.
Just like I don't want to climb hills for no reason, I don't want to carry weight for no reason either. But if I am going to be sufficiently more comfortable, especially when conditions are sketchy, I don't mind carrying more weight. There is some correlation between (less) weight and tour quality, but for me there is more of a correlation between comfort and tour quality. And weight and comfort are generally inversely proportional.