One of the "gatekeeping" responsibilities I have for the online article editing I do is to look out for writers who self-plagiarize and report them to the company.
When I first started this work, I took that responsibility seriously. And then I realized how much time it took, and the extent to which it could impact my hourly earnings.
Therefore, I never pick two very similar titles within roughly 24 hours. No doubt that writers grab them to make their work easier, and any self-respecting self-plagiarist would be a fool not to do the same.
I'm more interested in maximizing my income than I am in wasting time to determine whether someone appears to be guilty of S-P, and then having an internal debate about morality and my responsibilities.