Nothing has inherent value, given everyone assigns different values to things. What's gold and silver but shiny metal from the ground? You postulated that the only "real" value is value in energy, but given that everyone is liable to assign what their values are there's no such thing as "real" money. Money is just a promise of value in the future, and represents an intersection of values people have, along with a semblance of confidence backing it. People think that gold and silver are "real"; the reason gold and silver are considered to be credible is, interestingly, because people simply
believe that it is so, and invent all sorts of arguments to back it up. No money is real, because value is arbitrary, and confidence is the only thing that puts one form of currency over another. There's something that's quite fitting in this regard--the Greek word for money,
nomisma, interestingly enough is synonymous with "idea" or "imagination".
I think people get so caught up in all the details they just don't look at the base premises. Money is nothing but a promise of value, whether it's gold, bitcoins, dollars, yen, zimbabwe dollars, serbian dinars, or cattle. The kind of currency that exists simply reflects the common values a society holds, and just as how paper money was a reduction in physicality for an improvement in mobility over precious metals, many see bitcoin as the same process of reducing physicality and increasing mobility. When we all begin to understand that we're essentially exchanging a specific piece of data--namely how much value is owed--then it matters less and less how the data is conveyed.
I think whether Bitcoin is "real" or not is beside the point. If there's a community of people who think it's real who will gladly exchange their coins for 3d prints, and there are convenient means for a business to convert that payment (there are) into something they can hold (dollars etc.), then Shapeways should add functionality in for customers.
It appears that many people are getting really upset because they just don't agree with using Bitcoins, and that's fine as long as they don't try and impose that on other people. I'm just casually suggesting that Shapeways add more convenient payment methods for the subset of the community that uses Bitcoins. tKudos to innovo, by the way, for not immediately becoming enraged
Note that I'll probably be relatively inactive, so have a blast while I'm gone!