As with so many things Army, it depends on the theater of operations, the mission, the type of unit-mech, light,airmobile-and the commander. A good commander will look out for his troops, a bad one won't,and a sure sign of a bad commander is the extent to which he tries to ignore his troops' needs and logistical problems. In Vietnam water was a major problem,the brass-who for the most part did not share their troops hardships-either tried to impose water rationing or insisted that water purified with halazone tablets was perfectly satisfactory. Likewise there were constant orders-always ignored-for the troops not to carry so many C-rations-"You'll be resupplied!"
The effectiveness of helicopter resupply was greatly exaggerated, due to a variety of reasons such as weather, maintenance,enemy action,over optimistic assumptions-incompetence.
As Kraigwy said, your ruck was like your weapon-you NEVER parted with it.