You think that a wedding party in these traditional wedding-processional type weddings consists only of the groom and the bride?
Look, if this is trying to be some kind of humblebrag about ”hey, I am such a simple down-to-earth person that I don’t even get the concept of ceremonial formality and ritualized actions in a multi-participant ceremony”, okay, great, congratulations. But if you actually want to understand how a wedding rehearsal works and why it’s often done, maybe instead listen to the descriptions people are giving you instead of just insisting how unnecessary it all is?