We know that when many German soldiers were captured by Americans later in 1944, they were herded into open air camps that had no facilities. The prisoners were treated much in the way that they (the Germans) treated Soviet Army prisoners in that nothing was done for them. Many perished from starvation, disease and exposure to the elements. These camps were west of the Rhine (hence Rheinwiegenslager)
The lucky Germans who were captured earlier were sent to America or Great Britain where they sat out the war. The unlucky ones who were captured later could be starved or die of disease. Some who were captured were very lucky in that they got jobs with the American Army. They ate regularly, wore GI unforms with white "PW" painted on the back.
Only when the Morgenthau Plan (permanently destroy German industry and make it an agricultural nation) was abandoned in favor ot the Marshall Plan (rebuild destroyed nations) did things change.
So my question is did the US have the resources to build real camps and feed those PoWs? I know that it would take up resources to get lumber, set up facilities with proper kitchens, latrines, hospitals (to delouse, prevent dysentry, chlorea, typhus or other diseases) and this would draw from any offensive effort. Red Ball probably couldn't do both.
BTW, in my research I learned that everybody deliberated killed certain PoWs especially if they were thought to be snipers. No nation is innocent in that regard. To be fair, I also acknowledge that the Germans starved many of our guys and put them to work too. They got bread that also had "wood flour" (sawdust) and very watery soup. Herb Sheaner's book A Prisoner's Odyssey's gives a real good PoW account. Another is A Tale of Two Soldiers where a Jewish American sniper managed to conceal his Jewish heritage, was sent to a remote camp set up in a farm (to work as a farm laborer) where he was befriended by a recovering Luftwaffe lieutenant who conspired with him to escape the war with the German escorting "his" prisoners towards American lines and the American getting the German safely taken in as a prisoner (it worked they did).
Thoughts on Rhinewiegenslagers?