As ghostheads I felt for Ernie (if the situations and his reactions were genuine) "having" to go along with Walt's business plan, which at least for this episode (again if real) was not planned out or executed well. Near the end Ernie did seem to handle selling comics from an ice cream truck well enough. Ernie definitely had the funniest line when he was talking about not having to sell comics.
Ernie did seem to be a good sport overall, if he was ever serious about being part of Walt's idea, he seemed done and ready to leave.
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