Kilby writes: This is another one of CIDU Bill’s old drafts from 2019. The reference was so obscure that it might have been suitable for the authors to include their running gag with “Horace”, except that there would not have been enough space for that in a daily strip. (For those interested in background information, most of the sources that I was able to find listed the name as “Benjamin Marks“).
Comics I Don't Understand 
What are you saying about Horace? Is that something to do with Horace the Horse from “Dark Side of the ..”? IDU the post this time.
@ Dana – My footnote has nothing to do with the horse in Samson’s strip. The (human) character “Horace” is a running gag in “Barney & Clyde”:
I could find a Ben Marks who invented the Dollar Store con:
https://blogs.ancestry.com/cm/the-greatest-cons-5-cunning-historical-scams/
He is also mentioned in this article:
https://remixinghistory.com/leverage-and-the-big-con/
Not to be confused with this Ben Marks:
https://www.dailymail.co.uk/news/article-4028696/Con-man-stole-100-000-ex-girlfriends-decade-ago-old-tricks.html
Thanks to Kevin @3; those first two links are both much better than the one I included right below the comic.