A hospital stay is expensive, and the comic line goes:
 
“A hospital bed is a parked taxi with the meter running.”
 
Variety columnist and author Frank Scully (1892-1964) was credited with the line in the book The Modern Handbook of Humor (1967) by Ralph Louis Woods. American comedian and actor Groucho Marx (1890-1977) was credited with the line in 1969.
 
     
Wikipedia: Frank Scully
Frank Scully (born Francis Joseph Xavier Scully; 28 April 1892 – 23 June 1964) was an American journalist, author, humorist, and a regular columnist for the entertainment trade magazine Variety.
 
Wikipedia: Groucho Marx
Julius Henry “Groucho” Marx (October 2, 1890 – August 19, 1977) was an American comedian and film and television star. He was known as a master of quick wit and widely considered one of the best comedians of the modern era. His rapid-fire, often impromptu delivery of innuendo-laden patter earned him many admirers and imitators.
 
He made 13 feature films with his siblings the Marx Brothers, of whom he was the third-born. He also had a successful solo career, most notably as the host of the radio and television game show You Bet Your Life.
 
His distinctive appearance, carried over from his days in vaudeville, included quirks such as an exaggerated stooped posture, glasses, cigar, and a thick greasepaint mustache and eyebrows.
     
Google Books
The Modern Handbook of Humor
By Ralph Louis Woods
New York, NY: McGraw-Hill
1967
Pg. 177:
Hospital Bed: A parked taxi with the meter running. — Frank Scully
 
25 February 1969, Aberdeen (SD) American News, “Earl Wilson’s New York,” pg. 4, col. 5:
WISH I’D SAY THAT: Groucho Marx once described an expensive hospital stay: “A hospital bed is a parked taxi with the meter running.”
 
Google News Archive
12 May 1969, Pittsburgh (PA) Post-Gazette, “At Random” by Harold V. Cohen, pg. 33, col. 2:
Groucho Marx once described an expensive hospital stay this way: “A hospital bed is a parked taxi with the meter running.”
 
Google News Archive
11 May 1971, Sarasota (FL) Herald-Tribune, “It Happened Last Night” by Earl Wilson, pg. 6B, col. 8:
WISH I’D SAID THAT: Bobby Vinton deplores zooming medical costs: “At today’s prices, a hospital bed is like a parked taxi with the meter running.”
 
Google News Archive
22 April 1977, Boca Raton (FL) News, “Yule once a nude model” by Earl Wilson, pg. 17, col. 2:
TODAY’S BEST LAUGH: Any patient can tell you that a hospital bed today is the closest thing to a parked taxi with the meter running.—John Raudonis.
 
Google Books
And I Quote:
The Definitive Collection of Quotes, Sayings, and Jokes for the Contemporary Speechmaker
By Ashton Applewhite, William R. Evans III and Andrew Frothingham
New York, NY; Thomas Dunne
2003
Pg. 187:
A hospital bed is a parked taxi with the meter running. — Groucho Marx
 
Google Books
The Biteback Dictionary of Humorous Political Quotations
By Fred Metcalf
London: Biteback Publishing Ltd.
2012
Pg. ?:
A hospital bed is a parked taxi with the meter running.
Groucho Marx, 1890-1977, American comedian and actor