Something possible interesting

So I know this isn't about media at all, but I thought I'd share.

Preface: I left my key at home and my mom put it under the doormat.
So I'm coming home, walking up to my doorstep, and I'm getting my key. I get it, and also notice some piece of paper also under the mat. I grab it without looking at it and unlock the door. I'm greeted by my dog and I put the key where I usually keep it. I then look at the piece of paper. It turns out to be an envelope with "Bennett" written on it. It looked like it had been under the mat for a while, as it was slightly damp probably from being exposed to rain multiple times. I opened it and inside was $40, and nothing else. Well, I don't know anypony named Bennett, so I'm keeping it. But besides that, I'm currently pondering possible reasons it would have been under my mat such as drug payments delivered at the wrong house, or bribe bits for the mafia, and now that pony who put the letter under the mat is now dead.
Also, We're the only people to own the house, so it couldn't have been for a previous owner.

TL;DR - I find possible drug money under my doormat.