When you have, for an example, either an M4 or axe in your hands and you want to eat or use another one-handed item, the character puts the weapon between his legs and starts to use the item.
And when you add the belt, the character would put the weapon he is using on his belt to hang around until he/she is done using the item.
Also could you add a belt sometimes? I don`t think you could in real life use some sort of glue to stick the weapon on your T-shirt or jacket.
Could you devs add this to the next update? Please?