1. The original Liberator was designed to be used only few times in order to get real firearms from the occupying powers during WWII.
2. It was never really used in any theater.
3. It was quite small and concealable. This isn't.
I think it was more hoped that the original Liberator was only used a few times in order to procure better guns. Structurally, they could be used lots of times.
It was used in both theaters, though on a limited basis (~50,000 units) including being used in primarily Greece and China.
I believe it was said that it took longer to reload the Liberator than it did to produce the thing.
The Brits dropped loads of them over France for the French resistance to find and was intended to be used once to kill a German and take his rifle, and the ability to be reloaded was not something high on the priority list, the main priorities were to be small, very cheap, and very easy to manufacture.