Last year my son lost his phone while we were on vacation. I checked with lost & found at the venue we were at within 30 minutes of losing it, and again before closing, but no luck. It was a prepaid phone, so I didn't bother reporting it to the carrier, as there was only a $10 balance on it.
After we got home, I looked up the call records for calls made after he lost the phone, and started calling the numbers. On the first few calls I struck out, reaching someone wouldn't rat out their friend who had called them. On the next call I got lucky - reaching an honest grandmotherly-sounding woman who had overheard some kids talking about finding something. I called her back a few hours later and she had the phone in her hands, and the kids were in deep doo doo.
The following Monday I mailed here a prepaid priority mail box and she returned the phone to us, and refused any type of reward.
So, even though whoever finds your phone may not be a good samaritan, they may use it to call someone who is.
Good luck!