Keywords in a paper: to include or not to include? Are there some reasons to include them besides a historical tradion? Let's assume that it's not a requirement by the publisher.

There are some answers (such as this) which claim that keywords basically do not matter. However, I wonder if there are some empirical results or conflicting opinions on this. Perhaps they help with search engines?

My field is computer science, publishing mostly in IEEE conferences. Feel free to share experiences from other fields.
Here's one reason to include them:

In some fields, like biology, naming convention are lacking. You might use a specific word for a process, while other groups use another. By stating this other word in your keywords, researchers using that word will find your article/conference.