I know what you're thinking. The Merch has been in a TON of PA comics, come on! He's even in the PA store, representing different prices of gift certificates. This is true. The Merch frequently shows up on clothing and objects, particularly those belonging to children and other characters susceptible to his marketing campaign (including Annarchy). But the Merch has actually only personally appeared twice, in the comic that introduced him, and in an Unbelievably Merch Christmas.
Pic from The Merch.
#9
Eric Limer 
Max 
James Plafke 
Rollin Bishop 
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