Other mistake: In the scene where Don arrives at Dick's 'party', he looks at his non-existent watch. (00:13:25)
Continuity mistake: In the scene where the F.B.I. storm Dick's house, Charlotte's sleeves change length (i.e. being pulled up or like normal) throughout the entire scene. (00:20:00 - 00:20:30)
Continuity mistake: Mary's glass of wine goes from being almost empty to about half full during her conversation with Charlotte. In the same scene Charlotte goes to put the bottle down but in the next shot she is still holding it.
Answer: The writers often have Dick respond to Mary with a retort that he thinks is in the common vernacular but makes a mistake in wording that is often funny. Dick seems to be imputing a criticism from Mary and responds with a corruption of the more common "I'm going to wear your ass like a hat!" I doubt it has anything to do with owing taxes. Probably just one of the writers assuming a common regional phrase would be universally recognized.
That makes total sense. I always interpreted it as perhaps snowshoes are an expensive item, and given that he was blaming Mary for his newfound financial woes, he was equating her living off his generosity and used snowshoeing as a metaphor.
Phaneron