It's not supposed to be funny at all. The poster is not completely correct if he was referring to the sale of only the service plans. Actually, implied merchantibility applies to the sale of goods by merchants. Implied merchantibility basically states that a good should generally function for the purpose for which it was manufactured. If that T-Mobile phone you bought doesn't work, the merchant is responsible for "curing" the goods, or giving you a refund. There does seem to be a implied breach of various warranties, of which one of them is breach of implied warranty of merchantibility (refusing to take back certain items when they were defective originally), however, this does not apply to the sale of the service plans themselves. In any contract between a merchant and a merchant or non-merchant (the consumer in this case), there are always three kinds of implicit warranties, of which merchantibility is one.