I know and appreciate this, but this is exactly what I mean. This is a structural and organizational issue.
All Marines, who are not infantry by future MOS, go to Marine Combat Training (MCT) between Boot Camp (little infantry training) and their primary support MOS school. Infantry training continues for these Marines annually in order to enforce the infantry basics in patrolling, organic weaponry, etc. Marine infantry battalions are saturated with support Marines, because they need logistics, mechanics, communications, admin, etc. Ultimately, you are not going to find any Marine unit where their weapons are dirty, rusted out, or clueless as to their environments.
Infantry Marines skip MCT after Boot Camp, because their primary MOS comes from the School of Infantry (SOI). They live and breath infantry.
The Army does its soldiers a disservice by expecting so many of them to never see danger. And when they do, the "well, they aren't infantry" excuse is poor. This separation between Army infantry and "normal" soldiers has created a certain culture that forgives soldiers for being less-than soldierly. The Air Force can get away with this. You've seen their recruitment advertisements that imply that Airmen are either on special force missions or flying jets. This horribly represents what the vast majority of the Air Force does. The Air Force can look at their mass of Air Men and decide that the vast majority of them will never see any danger at all. They can focus soldierly training upon their AFSOC members, while separating the rest. The Army cannot afford to keep doing this to its soldiers. It all comes down to structure and recognizing branch mission. The Army, with it's far deeper vaults, can certainly afford to restructure in a way that treats every soldier as a soldier.