It's hyperbole to say it has no value. Retailers are free to reject old bills as they see fit and usually do.
I have never seen a retailer reject an old bill. Not saying that they don't or can't, but I do not think this could be called as they "Usually Do". I don't think that is true.
While on the subject a retailer doesn't have to accept US Currency at all old or new.
From the US Treasury Department:
https://www.treasury.gov/resource-center/faqs/Currency/Pages/legal-tender.aspx
The Coinage Act of 1965, specifically Section 31 U.S.C. 5103, entitled "Legal tender," which states: "United States coins and currency (including Federal reserve notes and circulating notes of Federal reserve banks and national banks) are legal tender for all debts, public charges, taxes, and dues."
This statute means that all United States money as identified above are a valid and legal offer of payment for debts when tendered to a creditor.
There is, however, no Federal statute mandating that a private business, a person or an organization must accept currency or coins as for payment for goods and/or services. Private businesses are free to develop their own policies on whether or not to accept cash unless there is a State law which says otherwise. For example, a bus line may prohibit payment of fares in pennies or dollar bills. In addition, movie theaters, convenience stores and gas stations may refuse to accept large denomination currency (usually notes above $20) as a matter of policy.