>>9615199Everyone, normalfag or not, puts up shit they find appealing but really has no direct purpose beyond 'looking nice' a.k.a. collecting dust.
My boomer parents have between them: model cars, paintings or artwork, odd sculptures or knicknacks from like Michaels, gifts or trinkets given to them by friends, or stuff like those Precious Moments figurines. My more normalfag friends have stuff like sports memorabilia, football helmets or baseball cards, hats/shoes they don't wear but display, etc.. My geek friends have statues or figures, art prints, replicas, niche interest stuff like wrestling masks on styrofoam heads among other things.
If you're asking why humans enjoy decorations, it's kind of a dumb question.