Often some poster in the UK would right in " I have a part from a Me109 that crashed here in 1941. It has a part number of XXXXX-123 Can anyone tell me what it is?" Now ending the quote. There are folks that have complete catalogs concerning every part that went into German aircraft ( kinky - I know.)
That would often bring a response: " Yes, you have part of a tailplane support, made in a French factory about 19XX". With a little checking, I found there was no effort by the French or Dutch or Belgies or any of the Nazi occupied nation the destroy their war industries. Hell, the good burghers of Rotterdam went all out to save those oil tanks to make a nice present to the incoming Germans.
Always keep in mind, there is no such thing as 'free trade', the real and more accurate term is 'labor arbitrage'.
In that it gave him employment? By tipping the scale of "labor arbitrage" in his favor?