1. I could not produce a receipt for any of my bikes with out a monumentous effort.
2. The paper receipts my LBS uses are old carbon copy receipts, and have the wrong phone # on them. So even if I found it, the # wouldn't pass muster.
3. All of their filing is paper filing, so calling to verify a sn would be a long wait.

So per your analysis, all of my bikes are stolen.