Enter, the poor 3D printer-less hero with big dreams. "Who can print me a doodad?"Occasionally in the past I've the last I've seen of this story is someone saying "message me", but I'm guessing that often times the final end is the same. Somehow there is still a myth that 3D printers are magic machines where you press the "Santa" button and get anything you want. "I'll pay for plastic" is a weak way of saying "I have no idea what this'll really cost."
A magi with a 3D printer steps forth and pronounces "What doodad are you thinking about?"
The hero presents a digital file to the magi who looks it over, feeds it into the skiener, and pops out an estimate. "Yes, this should take about 5 hours to print. I'd probably have to ask..."
"Oh" the hero interrupts. "Really? I... I was going get 20 of them."
"Well you can do multiplication, right? Add a little bit of time because I'm not going to always be there to pop one off the build platform and start the next build, but I can probably get them to you by..."
"You know, I.. may... uh... I gotta go."
kitlaan agreed to send me a print of a design I'd uploaded for a Chinese Chess set. He asked for $25 and I balked at first, but I realized this was the price of having something custom made for me. $25 is about half a roll of filament. Did it take half a roll of filament to make a Chinese chess set? No, of course not. But I wasn't paying for the plastic. I was paying for his time and the fact that he had a machine and I did not so he got to set the price. Unfortunately "you've got to pay to play" is still true. And as much as I'd like to be Father Christmas to everyone who wants a 3D print, reality doesn't line up with that.
There is hope. If you've made something from scratch people are much more willing to help you out. Everyone likes to be in the company of the productive creative. Also, making something cool helps. But if you're looking at a cereal sorter you read about on a blog and thinking "I need 20 of those for all my friends, and it's 3D printed so someone can pop those out like rabbits" be ready for a dose of reality.