Can someone explain why authors compare things such as humans and feelings to inanimate objects?

Its simply a metaphor, an analogy. Sometimes a metaphor can much mire accurately and understandably convey a feeling than any literal and direct explanation. Mostly metaphors ely on a common cultural background (try explaining a martian that there is an elephant in the room....) so the metaphor can actually be understood, and most humans tend to have similar sets of inanimate objects they know.

Thanks a lot. Others can still share their opinion on this thread as I am interested to know what you think. Thanks again builder396!

Maybe we do that because we see ourselves in everything, inanimate objects included. Similar to paleidolia (the psychological response to seeing faces and other significant and everyday items in random stimulus), perhaps, but in a literally sense rather than visually.

Humans are essentially very self-centered. We try to identify ourselves to literally anything. Perhaps that's why we likened our anger to erupting volcanoes, sadness to deserted towns...

Then again this is only my personal opinion.

Thanks Leisure for the elaborate explanation. It made me sit down and ponder about it briefly.