I've seen these before on here. I think most people are missing the point of the guns. It's not made to be a range toy or carry gun. The primary market (as another member mentioned) is for WWII buffs with piece missing from their collection. Of course, assuming they don't mind having non-original pieces in their collection. The sales of GI model 1911s, Kahr Thompsons and other (admittedly more popular) weapons have proven there is a market.
Originals are very scarce because (as mentioned before) most were dumped in the ocean and they (intentionally) weren't well made weapons. In other words, not alot of them are available for purchase. The real Liberators can sell for $1000+ and definitely are not recommended for use anymore.
I agree that $600 for a "non-firing" (unless you own a drill) replica is a little steep for it. However, it is a niche item that is made in small amounts by a small company. (Those three things all equate to higher costs on all sides.)
Mainly, I can see some WWII re-enactors buying them just to show-off to their other re-enactor buddies or some executive using it as an office decoration. I am for anything that is done tastefully, that helps people remember our veterans in a positive manner. Sadly, there are not a ton of WWII veterans still alive anymore. Something like this gun that a son (or grandson) could buy and put in a shadow box with his father's (or grandfather's) WWII pins, ribbons, medals is okay because it helps keep the memories and history.
-EdInk
P.S. (A rant about remembering veterans) The more time passes, the fewer tangible relics and less surviving people remaing from an event the quicker it and the lessons learned are forgotten by most people. People on here are pretty good about it BUT most people don't fully "stop and think" about how REAL people DIE in war.
When talking about WWII, the average person's mind thinks in "grainy Black and White" footage. God didn't "just get around to coloring the world" in the 1960s. Those were real living breathing people just like you and me. I think it is important to remember that fact. (I think "Saving Private Ryan" helped people "realize" it because it was in full color AND had a dramatic ending with the old man at the cemetery.) The same applies for people watching air to air combat footage (or other vehicles too). It wasn't just a plane, tank, etc that you see blown up. It was a pilot or crew that was killed too. I just don't like that people seem to forget about the PEOPLE.
It's like the saying goes, "The death of one is a tragedy. The death of a million is just a statistic."
Sorry for the rant.