I was gonna just say "the wife is right" which should have been immediately obvious, but I'm glad Adam took time to tell you why.
I do the same with all my pics. I don't need the multiple .psd files that I create along the way, they're just for workflow or "incremental backups". I just need the hard copy and the raw file(s). Usually the final product ("hard copy", beit on disc or paper or whatever) is for someone else and I have no interest or need for it, anyways.
I keep the raws in case someone wants more work done later.