Several commentators have argued that the Economics-Made-Fun (“EMF”) genre contains very little actual economics. As such, it would seem that criticisms of EMF do not apply economics more broadly. In this paper I take a contrary view, arguing that, in fact, at a deep conceptual level, the engine of EMF analyses is precisely the engine of mainstream economics. Specifically, I argue that both EMF and mainstream economics rest on a conceptual foundation known as the Principal of the Substitution of Similars (“PSS”). Understanding how PSS leads EMF practitioners to make claims well beyond what is warranted by their analysis also offers insight into how PSS leaves mainstream economists in danger of overestimating the power and scope of their analyses. I explore the consequences of such problems through an example of economic analysis of the U.S. housing market in the lead-up to the recent financial crisis.