People often save items (such as baseball cards) with the belief that some day they will be worth a larger sum of money. What about someone who saves money?
 
“Save yer money. Some day it may be worth something” is a joke of unknown authorship that has been cited in print since at least 1951. Savers, however, often find that the purchasing power of the saved money has decreased (and not increased).
 
   
2 February 1951, Zanesville (OH) Signal, “On Broadway” by Walter Winchell, pg. 4, col. 4:
At Cafe Tokay: “Save yer money. Some day it may be worth something.”
 
18 May 1953, Chicago (IL) Tribune, “In the WAKE of the NEWS ” by Arch Ward, pg. C1:
It’s smart to save money; some day it may be worth something.
 
25 June 1953, Manitowoc (WI) Herald-Times,  “Little Liz” comic strip, pg. 8, col. 3:
Everyone should try to save some money—some day it may be worth something.
 
7 September 1958, Boston (MA) Sunday Herald, “Life Returns To High Gear” by Marjorie Mills, sec. 5, pg. 7, col. 1:
Well, save money if you can, kids. Some day it may be worth something again.
 
24 October 1959, The Progress (Clearfield, PA), pg. 4, col. 6:
We’re trying to save money. Who knows? Some day it may be worth something.
 
Google News Archive
31 March 1960, Beaver Country Times (PA), Earl Wilson entertainment column, pg. 11, col. 5:
TODAY’S BEST LAUGH: Some people will gamble on anything. Now they’re beginning to save money on the chance that some day it’ll be worth something, .
 
17 January 1961, Chicago (IL) Tribune, “Front Views & Profiles” by Kay Loring, pg. A2:
Jack Herbert observing that it’s smart to save money; someday it may be worth something.
 
20 March 1973, Boston (MA) Herald American, pg. 21, col. 4:
As Norm Nathan quipped on the radio the other morning, “Save money. Some day it may be worth something again.”
   
Google Groups: alt.quotations
Rod Carty
6/4/98
(...)
Save your money - some day it may be worth something.
 
Google Books
Borrowed Money
By Robert Shaver Martin
Bloomington, IN: 1stBooks
2003
Pg. 72:
“My grandmother told me to save it saying it might be worth something some day.”