Although it's unlikely to really be a useful interaction, even in the rare games where the necessary combination comes up, there is an interesting quirk with Highwayman + Spoils + Crypt, namely, that if your opponent has played a Highwayman, and a Spoils is your first Treasure, it actually ends up staying in play, so that it can be put in your Crypt (or topdecked by Herbalist for that matter)
I suppose another possible edge case for the Highwayman/Spoils interaction might be activating Magic Lamp
