“Racetrack—A place where the windows clean the people”

Paul H. Gilbert’s syndicated newspaper column of “Daffynitions” (humorous or “daffy” definitions) included the following in October 1947:
 
“RACE TRACK: A place where the windows clean the people.”
 
The Reader’s Digest credited entertainment columnist Earl Wilson in 1947, but the style of the joke (a “daffynition”) probably indicates that Gilbert told it first.
 
Many other comedians have been credited with the joke, including Danny Thomas (1912-1991) in 1950, Eddie Cantor (1892-1964) in 1954, Joe E. Lewis (1902-1971) from the 1955 biography The Joker Is Wild, and Bob Hope (1993-2003).
 
 
Old Fulton NY Post Cards
29 October 1947, Philadelphia (PA) Inquirer, “Daffynitions,” pg. 33, col. 7:
RACE TRACK: A place where the windows clean the people.
   
Google Books
The Reader’s Digest
Volume 51
1947
Pg. 83:
Racetrack — where the windows clean the people (Earl Wilson).
 
2 March 1950, Springfield (MA) Union, “Walter Winchell On Broadway,” pg. 11, col. 4:
Danny Thomas’ pepigram about race-tracks: “Where the windows clean the people!”
 
Hathi Trust
Comic Dictionary
By Evan Esar
New York, NY: Horizon Press
1951
Pg. 240:
race track.
1. Where dollars and sense seldom appear together.
2. A place where the windows clean the people.
 
Google News Archive
25 October 1951, Milwaukee (WI) Sentinel, “Along Amusement Row” by Buck Herzog, pt. 1, pg. 17, col. 4:
“Pappy’s: Buckets Goldenberg says a racetrack is where the windows clean the people.
 
7 February 1954, Seattle (WA) Times, “Daffynitions” by Paul H. Gilbert, Magazine, pg. 12, col. 3:
RACE TRACK: A place where the windows clean the people.
 
Google News Archive
12 October 1954, St. Petersburg (FL) Times, “Crazy Over Horses” by Eddie Cantor, pg. 23, col. 3:
Everybody knows the race track is the only place where the windows clean the people!
 
Google News Archive
2 October 1969, Milwaukee (WI) Sentinel, “Today’s Chuckle,” pg. 1, right masthead:
A racetrack has been defined by at least one knowing fellow as a place where the windows clean the people.
 
Google Books
The Gigantic Book of Horse Wisdom
Edited by Thomas Meagher
New York, NY: Skyhorse Publishing
2007
Pg. 464:
This is the only place where the windows clean the people.
— JOE E. LEWIS, ON RACETRACKS
     
Twitter
Sports Quotes
‏@sports_quotes
“A place where the windows clean the people.”—Bob Hope, on his definition of a race track. #KentuckyDerby
4:10 AM - 5 May 2013
 
Twitter
Johnny Love
‏@StribLove
“The racetrack is the only place where the windows clean the people” Joe E Lewis
6:49 AM - 16 Oct 2013