"wHy dO i nEeD a PaSsWoRd"
I dunno, so no one else can access your account and mess with your favorites, comments, impersonate you, or otherwise make your life hell on this site? And if you're an artist, it makes it that much worse if you decide to upload art and then someone decides to start spamming non-pony or otherwise bannable content and gets your account yeeted.
Just a thought though, maybe user accounts are just dumb and we shouldn't have them at all, we'll all just be anons! /s