Yes, as long as you have a copy of the receipts, they'll help you to recover your devices.
I lost an Apple device once (several years ago) in a public place. A couple of days later I got a customer service mail from Apple asking for feedback on a recovery service for the device. So clearly whoever found my device was able to get it unlocked by Apple, or at least get it reset by them to the point they could use it.
That was a disappointing experience. Mailed Apple, but no reply. Fortunately not much personal data on the device. Hopefully things are stricter now.
Although this points to how it's always something of a tradeoff. Absolutely require people to have certain specific information and those who don't have it are pretty much SOL. Perhaps you can make exceptions that require showing up somewhere and present physical ID. But the easier you make it to tell a sob story over the phone/email to get an exception to policy, the easier you make it for unauthorized people to take advantage.