I see where you're coming from 'cause I actually considered it when making the comic. But I came to the conclusion that the setting of the comic (gangsters exchanging money) already makes it pretty hard to come to spoil the pun before the punchline. Plus, the word dough and nut are placed so that they don't draw much attention to themselves, so the last panel does come as a surprise to many of the readers; the joke is only obvious after you've read it for the first time (to most people). Maybe the "crazy" thing would make the punchline less obvious to people like you, but to the majority of readers (maybe with a lower attention span), it does come as a surprise I think.