“Why are poets poor? Because rhyme doesn’t pay,” an old joke has it, punning on “crime doesn’t pay.” “Afterthought: Who said rhyme doesn’t pay?” was cited in the Brooklyn (NY) Daily Eagle in January 1938. The line was popularized in June 1938, when someone in Hollywood asked Dorothy Parker (1893-1967) why she stopped writing verse. “Because I have learned that rhyme doesn’t pay,” Parker replied.
 
Rhyme does pay for successful songwriters and Broadway lyricists.
 
   
Wikipedia: Dorothy Parker
Dorothy Parker (August 22, 1893 – June 7, 1967) was an American poet, short story writer, critic and satirist, best known for her wit, wisecracks, and eye for 20th-century urban foibles.
 
From a conflicted and unhappy childhood, Parker rose to acclaim, both for her literary output in publications such as The New Yorker and as a founding member of the Algonquin Round Table. Following the breakup of the circle, Parker traveled to Hollywood to pursue screenwriting. Her successes there, including two Academy Award nominations, were curtailed when her involvement in left-wing politics led to a place on the Hollywood blacklist.
 
Dismissive of her own talents, she deplored her reputation as a “wisecracker”. Nevertheless, her literary output and reputation for her sharp wit have endured.
     
Brooklyn Newsstand
24 January 1938, Brooklyn (NY) Daily Eagle, “Radio Dial Log,” pg. 24, col. 3:
Afterthought: Who said rhyme doesn’t pay?
 
16 June 1938, Seattle (WA) Daily Times, “Along Film Row” by Richard E. Hayes, pg. 8, col. 7:
Down in Hollywood the other day someone asked Dorothy Parker why she has written no verse recently. Dorothy answered that she has “discovered that rhyme doesn’t pay.”
 
30 June 1938, Morning Advocate (Baton Rouge, LA), “In Hollywood” by Paul Harrison (NEA Service Staff Correspondent), pg. 4, col. 4:
Dorothy Parker hasn’t penned any poetry lately. Asked why, she said, “Because I have learned that rhyme doesn’t pay.”
 
13 November 1942, Circleville (OH) Herald, “You’re Telling Me!,” pg. 4, col. 6:
The poet who must go back to work at something else in order to eat has also learned the bitter lesson that rhyme does not pay.
 
Google Books
Sales Management
Volume 55
1945
Pg. 62:
John Love says the line, “Rhyme does not pay,” recalls that Lord Dewar once remarked that “poets are born — not paid.”
 
OCLC WorldCat record
Rhyme doesn’t pay.
Author: Harry Cross
Publisher: Cross, 1951.
Edition/Format:   Print book : English
 
OCLC WorldCat record
Rhyme doesn’t pay
Author: Omar K Bram
Publisher: Cambridge : [publisher not identified], 1951.
Edition/Format:   Print book : Fiction : English
 
Google Books
The Book of Poisonous Quotes
By Colin Jarman
New York, NY: McGraw-Hill
1993
Pg. 84:
Poetry is living proof that rhyme doesn’t pay.
Anonymous
 
OCLC WorldCat record
Rhyme doesn’t pay
Author: Gordon T Sprunger
Publisher: Morgantown, PA : Masthof Press, 2001. ©1997
Edition/Format:   Print book : English
 
Google Books
Music:
A Book of Quotations
Edited by Herb Galewitz
Mineola, NY: Dover Publications, Inc.
2001
Pg. 56:
The success of today’s rock songs proves one thing— rhyme doesn’t pay.
EARL WILSON
   
Twitter 
chaz graner
‏@chazmo2222
Poetry is living proof that rhyme doesn’t pay…
1:11 PM - 4 Jan 2015
 
Twitter
Gaz_943
‏@garethjones934
Question: Why are poets always so poor?
Answer: Because rhyme doesn’t pay.
10:35 AM - 21 May 2015