>>723786204
Invaders use the level to their advantage because that's how multiplayer is designed. The mutually exclusive advantages that each multiplayer party gets are as follows.
Invaders:
>can use (some) enemies against the host and their summons
Hosts:
>can be higher level than the invader
>can have a higher weapon upgrade level than the invader
>can summon up to two players who completely ignore level and weapon level restrictions, stat requirements, and weight
>these players can one-shot invaders depending on the level range
>can infinitely summon hunters who, because of the way the matchmaking formula works, can daisy chain the host's level advantage (WebM related)
>can send their summons home to deny healing flasks to the invader
>can infinitely resummon their summons

Every other advantage one party has over the other applies to both, like having items that aren't appropriate to the level they're playing at, cheated consumables, etc.