You had run out of pants. That was a bad thing to run out of. So, you ended up grabbing whatever you could find. The pants were baggy and didn't hold onto your waist at all so you had to grab a belt.

You walked out to a debrief with Grinch giving a weird look becuase it was obvious those weren't your pants. Azur minding his own business, Zane trying to not judge you so hard, and Mace trying to figure out if those are his or not.