A bit confused about weapon drop

I’ve been watching some Multiplayer matches, some were the classic Slayer and some were the new Slayer where you get kills & an Ordinance drop. My question is, do normal map items drop down or do they just spawn on normally like the other Halo games? It seems to me the normal items like weapons and grenades will just spawn, while in that one mode, your ordinance will drop by near you. What do you think?