When it comes time for me to publish my changes, I very much do not want those unpublishable intermediary states going out into the world. Rebase lets me break apart and combine them into rational, test-passing changes that have cogent, readable commit messages instead of "blah", "blah again", "what the hell i forgot to frob the flubulizer!?", etc.
In sum, yes it's a heavy-handed tool. Yes you're "destroying" history, but often that history is extremely ephemeral and mundane and not germane to the actual meaning or effect of the change.