The conclusion to Halo 4: Forward Unto Dawn gives a glimpse into what it would be like to be one of those UNSC soldiers that occasionally accompany Master Chief on his adventures. I can't speak for others, but I barely notice when one of those soldiers dies while playing a Halo game. Thankfully for Forward Unto Dawn, the real Master Chief seems to care a great deal about these four cadets and their survival.
For those who haven't been following the series, Forward Unto Dawn is a live-action web series that follows the life of cadet Thomas Lasky at the UNSC military academy. The series, as promised, ties-in to the beginning of the Halo 4 story, which begins in less than one week. The previous episodes of the series, including the short character vignettes that proceeded it, can be found here.
When we last left Lasky and his remaining squad mates, they had escaped the ruined academy and made off with a warthog for the pelican landing zone. As Lasky learns to drive the vehicle, the cadets put their training to use against Jackals hiding in the forest. Master Chief mans the guns, but we all know what happens when you let the UNSC soldiers drive in the games. It's clear from cannon that Master Chief survives to participate in the original Halo trilogy, but if the cadets hope to survive they'll have to become soldiers - because they're being hunted.