I suppose, from a strictly bottom line standpoint (EDIT: and questions of right or wrong aside), it depends on whether a custom shirt shop can give you what you want cheaper than Topatoco can. And maybe there is, or isn't, a copyright issue here. But QC merch, I'm given to understand, is a significant part of how Jeph supports himself and his wife, and discussing how to circumvent it -- on a forum he sponsors -- is a pretty shitty move.
-- AMENDED to disambiguate my opinion.