“Pie rates of Penn’s aunts” (pun)

The Pirates of Penzance; or, The Slave of Duty is a comic opera with music by Arthur Sullivan and libretto by W. S. Gilbert, opened at the Fifth Avenue Theatre in New York City on December 31, 1879. A pun on the title was printed as early as January 9, 1880, in the Stamford (CT) Advocate:
   
“The new opera enlightens us upon the Pie-rates of Penn’s Aunts, but says never a word concerning the prices charged by his sisters and his cousins.”
 
“Pie rates of the Caribbean” is a similar pirate pun.
       
 
Wikipedia: The Pirates of Penzance
The Pirates of Penzance; or, The Slave of Duty is a comic opera in two acts, with music by Arthur Sullivan and libretto by W. S. Gilbert. The opera’s official premiere was at the Fifth Avenue Theatre in New York City on 31 December 1879, where the show was well received by both audiences and critics. Its London debut was on 3 April 1880, at the Opera Comique, where it ran for 363 performances, having already been playing successfully for more than three months in New York.
         
9 January 1880, Stamford (CT) Advocate, pg. 2, col. 5:   
The new opera enlightens us upon the Pie-rates of Penn’s Aunts, but says never a word concerning the prices charged by his sisters and his cousins.
 
22 January 1880, St. Joseph (MO) Weekly Gazette, “Our Breakfast Table,” pg. 6, col. 6:
Who can tell what were the pie rates of Penn’s aunts?
 
Google Books
21 February 1880, The Musical Record (Boston, MA), “The Major and Minor,” pg. 322, col. 3:
A Bostonian has written a burlesque on Messrs. Gilbert and Sullivan’s latest opera, calling it “The pie rates of Penn’s aunts.”
 
12 May 1880, Detroit (MI) Free Press, “Personal,” pg. 5, col. 2:
The Pie rates of Penn’s aunts were twenty cents each.
   
26 July 1959, New York (NY) herald Tribune, “‘Pun my word!” by Bennett Cerf, THis Week magazine, pg. 4, col. 3:
In no time flat, the good citizens of Quakertown were discussing only one topic: the pie rates of Penn’s aunts!
 
6 May 1973, The Sun (Baltimore, MD), “Heard Any Nine-Mile Puns Lately? Ralph Has” by Ralph Reppert, magazine sec., pg. 49, col. 2:
Gilbert and Sullivan wrote an operetta about the famous wall and called it “The Pie Rate of Penn’s Aunts.”
 
Twitter
John Ashton‏
@ickledot
Noel Edmunds around 1972 - does anyone remember the Pie Rates of Penn’s Aunts joke?
2:21 AM - 30 Dec 2008
 
Twitter
Fortune 140‏
@fortune140
Penn’s aunts made great apple pies at low prices.  No one else in
town could compete with the pie rates of Penn’s aunts.
4:33 AM - 16 Jun 2009
   
History Today
Victorian Jokes: The best in 19th-century humour
By Lee Jackson
Posted 4th October 2011, 8:50
(...)
If William Penn’s aunts kept a pastry shop, what would be the prices of their pies? The pie-rates of Penn’s Aunts.
   
Google Books
Jokes and Puns
By Ronn Foster
New York, NY: Page Publishing, Inc.
2015
Pg. ?:
They put their delectable concoctions on the market at cost—and then proceeded to reduce the price five cents a day.
 
In no time, the good citizens of Philadelphia were discussing only one topic: the pie rates of Penn’s aunts.
 
Twitter
Quote Bot‏
@bruhinb_quotes
Quote Bot sez: Penn’s aunts made great apple pies at low prices. No one else in town could compete with the pie rates of Penn’s aunts.
11:00 PM - 12 Sep 2017