Every 75 years?
I was a bit obtuse in my comment. I tried to equate a coffee machine - a tool to make coffee - with a high quality "shiny finish" wrench - and that a scratch free wrench is a sad wrench (sort of like a clean mountain bike is a sad mountain bike).
Actually, you were quite clear - and I agree with you completely. No one would ever mistake my tools for new, and they're very happy fellas because they were born to be used!
I'm a professional musician and have owned and played many fine "vintage" instruments, many of which I bought new (I started playing in 1959). I'm always amazed at the "collector" who pays a huge premium for a pristine 1950 Fender or Gibson that doesn't have a mark on it. There are only 2 reasons for a 65 year old guitar to look brand new - either it was never played or it's a fake. And there are only a few reasons why a guitar like that was never played, starting with the fact that it felt and/or sounded terrible (remember that these were all hand made to some degree, and variation was inevitable - for example, some hand wound pickups sounded fabulous and others just lacked great tone). There are some who keep having their instruments refinished when they get marked up, which means that they're not "all original" despite the claim to the contrary - and even the best refinish is hard to disguise. Regularly polishing out the marks on a coffee machine in an attempt to keep it "like new" is marked with the same stigmata and is a similarly foolish endeavor, in my opinion.
I've not heard of anyone's faking a good espresso machine (although it wouldn't surprise me if there are counterfeits out there), so the main reason for a SS DB machine to lack any signs of use is that it was never used. "Why not"? Even if a novice owner tried and failed to make good coffee and just gave up, there would be some signs of use - and this is true for guitars, bikes, cars, audio equipment, and every other toy in the world.