It is infringement not theft despite the extensive rhetoric to conflate the two. If something is stolen they no longer have it. If something is infringed then it is only their exclusivity undermined.
Say you own the Batmobile from a particular Batman movie and all rights to its reproduction. If make an exact copy of your Batmobile you would still have it in your garage. The value might be undermined some because it is a substitute good but only one was involved in the filming.
Infringement may still be wrong (it varies by circumstances just like how breaking a baptismal font to save a boy from drowning isn't simple sacrilegious vandalism) but it isn't theft.
Say you own the Batmobile from a particular Batman movie and all rights to its reproduction. If make an exact copy of your Batmobile you would still have it in your garage. The value might be undermined some because it is a substitute good but only one was involved in the filming.
Infringement may still be wrong (it varies by circumstances just like how breaking a baptismal font to save a boy from drowning isn't simple sacrilegious vandalism) but it isn't theft.