I can answer your question without being smug.
I want to address one post specifically here:
"Build quality
Material quality
Pay of the people who build them
Supporting the local economy (for the U.S. folks in this case)"
These are all true, however, the real reason one enjoys smoking out of a rig has nothing to do with those things, and everything to do with function. Yes, you are paying money based on those things, and they should matter, but ultimately a rig is considered a good smoking piece regardless of those things. It is the function that matters and that's why designs from Mothership, Mobius and David Goldstein are replicated so much.
A "china glass" quality bong can still function properly as the original design was intended to. Will it ever be a complete match? Nope. But that's where you take into account the price difference to the function difference. If it functions close enough to the original but not quite like it, I would be willing to pay a lower price for it. Someone brought up an example with cars. Let's say you want to run 9 seconds in a 1/4 mile, there are many different way one can achieve that goal. Spend 200k on a super car, or build a 4k dollar Civic. The goal can be achieved while the quality varying vastly.
I've also bought American glass with "china glass" quality. The stigma about "china glass" isn't necessarily where it's made, but the quality of the product. Paying such a low price you are paying for thinner, more fragile glass, containing more imperfections, sometimes not properly aligned joints, etc. But again, at the end of the day do these things affect function? In my experience, not unless the overall design is really off from the original and/or diffusion design is not the same.
A side note before people get really nasty with me too, this is coming from a guy that has invested thousands of dollars in his collection. My collection includes 3 Mobius glass rigs, Sovereignty, David Goldstein, Seed of Life custom, etc. I appreciate and invest in high quality build/material and support American glass makers. However, I do also purchase cheap "china glass" but I do so only if I see how they function. It is not only worth the money (you literally saved $400+) but it gets the job done anyway.
I don't like the negativity coming from this group, the elitism is nasty. I think 420engineer had zero intention to spark any friction or animosity here, it just wasn't deserved at all.