Well, this will be anticlimactic for most, but the mailbox poopers have been revealed to be my good friends James and Jill. They sent me an email with the following:
We hope you enjoyed the lovely present we sent you. We saw it and thought of you. The checkout process had no way to include a note.
So the real culprit here is a terrible checkout process. I hope we’ve all learned something. Namely, that it’s possible to send a stuffed pile of poo emoji through the mail, to anyone you love (or hate). Well, if this site’s faithful readers hadn’t managed to buy up so many that they’d sold out, anyway.
Y’all have a lot of disposable income.