Their term "stray" makes it sound like he escaped or was dumped- but who knows? Someone probably changed their mind & became afraid when he got bigger, or their room-mate or spouse objected (seeing the feeding response)- this wouldn't be the first time that happened- or they may have claimed it belonged to an ex-roommate that moved out & was left behind, or gave some other such story. Or like you said, just left behind... I'm glad he's got a home now, & no, I wasn't going to call you a hoarder, lol. Nice looking boa, & appears healthy, at least in photo.