Thanks Otto!
Yes. Many of the captured smallarms if I understood it right however did end up with like support units or units that didnt see quite much of smallarms combat compared to front units like you you said, coast defenses, luftwaffe, guard units, navy and training programs ( see picture below!)
However towards the end of the war many of these support units went to the front because in lack of units ;>
Iam pretty sure front unit got a great quantity of captured smallarms as well and as we all know these are the guys who captured them in the first place so they sure had their share
Here is a great picture of a Navy man with a thompson m1a1 smg that I got from axishistory forum!