I think part of this trap was due to how FB encouraged people to "friend" as many people as they could..

At the height of my Facebook usage, I had less than 100 connections, because even back then I only stayed connected with people I was trying to maintain meaningful connections with.

No co-workers I didn't see socially, no one I went to high school or university with but didn't still keep in touch otherwise, etc..

So I rarely saw "junk" on my feed that was totally irrelevant to me, but it still happened sometimes..