Bishop Studio points out that there is "always room in the soldier's kit for portraits of the home folks".  Surely you don't want your son to be home sick and not be able to look at you?

But It's Wafer Thin

Supplying the soldiers was a boon to business.  Where several major national companies won contracts, many of the other needs of the troops had to be privately supplied.  Countless ads began to show up in newspapers and magazines for mess kits, pens, photographs, pocket knives and camp stoves.  Goods which barely were mentioned as they were ordinary and mundane soon found a spotlight.  While there was ample shipping available to soldiers at camp, it was much more difficult for obvious reasons to deliver packages to the lines, thus purchasers were encouraged at every turn to supply their boys before they shipped out. 

This economic boom was already in effect before we entered the war itself.  Great Britain and France were heavily invested trading partners, and the U. S. supplied most of their war needs as well.  This demand played out as a 44 month flourish which pulled America right out of a Recession. There can be no real doubt that the Allied forces relied upon American industry, but the individual soldiers in the trenches certainly recieved gifts and packages from "across the pond".