This is not a bug but status-bydesign: The system can't know that you're a "good user" who just wants to fix a typo or something similar. The rationale is that you might as well be a "bad user" who wants to cripple the titles of his questions for whatever reasons. Yes, this rarely happens, but if it does, then it's really bad. And in this case it's an advantage that the question is bumped: Other will see what happened and can revert a bad edit.
EDIT: Asaf made a point in his comment about a rep threshold: That might be an option, but in my opinion only under heavy restrictions. Just an idea (not sure if I like it myself): If a user with more than 5000 rep edits their own post, and it's a minor edit with, say, at most 5 characters difference, then the edit appears in the revision history as "minor edit" without bumping, but the next minor edit will still bump the post.