“What do you call an ice cream truck operator?”/“A sundae driver.”

A “Sunday driver” is someone who drives slowly (and often poorly), There are several puns about a “sundae driver.”
 
An early pun involves a driver who eats ice cream. “A Logansport (Ind.) motorist lost control of his car, he told the judge, because he had eaten too much ice cream. And the Springfield Union man remarks, ‘Ah, yes, the sundae driver,’” the “Senator Sopaer newspaper column (by H. V. Wade) printed on July 13, 1951. “He who eats ice cream in a car is a sundae driver” has been a Bazooka Joe bubblegum joke since at least 1993. “Confucius say: He who eats ice cream in car is a Sundae Driver” was posted on the newsgroup rec.humor on November 6, 1995.
 
“Good Humor man: Sundae driver (Edward Nictupski)” was printed in The Reader’s Digest in 1966. Good Humor ice cream trucks were very popular in the 1960s. “Nit: What do you call the man who drives a truck through town, selling ice cream? Wit: A sundae driver” was printed in Boys’ Life magazine in June 1979. “What do you call an ice cream truck operator?...a sundae driver!“was posted on Twitter on August 10, 2011.
 
“Sundae Driver” is also a drink combination of a screwdriver (vodka and orange juice) and a sundae. “Sundae Driver…Vodka, orange juice, and ice cream” was printed in Omni magazine in July 1991 (in the issue dated August 1991).
 
           
Wikipedia: Sundae
The sundae ( /ˈsʌndeɪ, ˈsʌndi/) is a sweet ice cream dessert. It typically consists of one or more scoops of ice cream topped with sauce or syrup, and in some cases other toppings including sprinkles, whipped cream, peanuts, maraschino cherries, or other fruits (e.g., bananas and pineapple in a banana split.).
 
Wiktionary: Sunday driver
Noun
Sunday driver
(plural Sunday drivers)
1. (idiomatic) One who drives slowly, as for leisure or sightseeing.
2. (dated) One who drives infrequently, and often poorly.
         
13 July 1951, Durham (NC) Sun, “Senator Soaper” by H. V. Wade, pg. 4, col. 2:
A Logansport (Ind.) motorist lost control of his car, he told the judge, because he had eaten too much ice cream. And the Springfield Union man remarks, “Ah, yes, the sundae driver.”
     
Google Books
The Reader’s Digest
Volume 89
1966
Pg. 94:
Good Humor man: Sundae driver (Edward Nictupski).
     
14 March 1969, The Journal Herald (Dayton, OH), “Test Your English” by Carroll H. Jones, pg. 58, col. 2:
Good Humor man: sundae driver.
 
Google Books
June 1979, Boys’ Life, “Think & Grin, pg. 74, col. 1:
Nit: What do you call the man who drives a truck through town, selling ice cream?
Wit: A sundae driver. — Charles Lewin, Burnt Hills, N.Y.
 
Google Books 
Remember the A la Mode:
Riddles and Puns

By Charles Keller
Englewood Cliffs, NJ: Prentice-Hall
1983  
Pg. ?:
What do you call a man who drives an ice cream truck?
A sundae driver.
     
31 July 1991, The Province (Vancouver, BC), “Daily Planet” by Peter Clough, pg. 45:
ON THE RACKS: It must be silly season. Omni, normally a journal of popular science, asked readers to come up with drinks meant to be read, not drunk. For example, when you mix a Midori and Dawn dishwashing liquid you get Honeydew the Dishes. When you mix vodka, tomato juice and a spoonful of sugar, decorated with a paper umbrella you get a Mary Poppins. When you mix vodka, orange juice and ice cream you get a Sundae Driver
 
Google Groups: rec.humor
Mixed Drinks
Steve Monson
8/12/91
In this month’s issue of _Omni_ magazine there appeared the results of their latest “Name the Mixed Drink” contest. With no further ado, here the names are, in alphabetical order. Which one do you think was the winner
(...)
Sundae Driver….........Vodka, orange juice, and ice cream
     
Google Groups: rec.food.drink
Mixed Drinks
Arno Schaefer
3/4/93
(...)
|> Sundae Driver….........Vodka, orange juice, and ice cream
—-^
This is a popular variation of ‘Screwdriver’, called ‘Screwdriver on Ice’ and certainly does not belong to rec.humor.
 
BTW: try it, it tastes great!
   
1 May 1993, Oshkosh (WI) Northwestern, pg. 1, col. 3:
Has anyone checked out Bazooka Joe lately? (...) An example is the fortune on the bottom: “He who eats ice cream in a car is a sundae driver.”
 
Google Groups: soc.culture.indonesia
refreshment for the netters
EKO SETIAWAN - DUDE!
8/1/93
(...)
What do you call the ice cream truck man?
-A sundae driver.
 
Google Groups: rec.humor
Confucius say ...
Zul
11/6/95
(...)
Confucius say: He who eats ice cream in car is a Sundae Driver.
 
Google Groups: rec.humor
Toward a Canonical “Confucius Say”
William Boyd Secrest, Jr.
1/15/96
(...)
CONFUCIUS SAY: He who eat ice cream in car is a sundae driver.
     
Google Groups: alt.humor.puns
Dairy puns
Richie !
7/9/97
(...)
>  Is the Good Humor man a sundae driver?
>
No, but I’ve heard he was a pain in the dairy-air.
       
Google Groups: alt.jokes
Silly Clean Jokes1
Grandad Skip
10/10/99
(...)
Q. What do you call the ice cream truck man?
A. A sundae driver.
 
Google Groups: alt.pub.thistle+joe
Additions to the drink list.
W John Bodin III
1/22/00
GUIDE TO NEW MIXED DRINKS
(...)
Sundae Driver…............Vodka, orange juice, and ice cream
   
Twitter
✌🏼
@SuzanneBiello
Sundae Driver = Vodka, orange juice and ice cream #drinks101
10:32 PM - 25 Apr 2010
     
Twitter
Jesse Greathouse
@jessegreathouse
“He who eats ice cream in a car is a sundae driver”—Bazooka Joe
12:46 PM - 28 Dec 2010
   
Twitter
Christine Rea
@dippindairy324
What do you call an ice cream truck operator?...a sundae driver!  Chime in if you have tried our new Pretzel Caramel Sundae. http://ow.ly...
11:30 AM - 10 Aug 2011
   
Twitter
Nesper Sign
@NesperSign
What do you call an ice cream truck man?  A sundae driver!
4:24 PM - 18 Jan 2012
 
Twitter
1SafeDriver.com
@1SafeDriver
Klondike bar-tender: How did you end up with hot fudge all over you?
Good Humor Man: I ran into a Sundae driver!
#addicecreamimproveanything
6:10 PM - 7 Jun 2017
 
Twitter
Dick Coughlan/Brother Neuro
@DickCoughlan
Replying to @c0nc0rdance
The other day I got stuck behind this really slow car on the freeway, As I got closer I noticed the car was made out of ice cream with a cherry on top…I thought “Typical Sundae Driver”
11:46 PM - 6 Apr 2018
     
Twitter
Matt Paasch
@mattpaasch
Just saw a guy driving while eating ice cream. Be careful of those sundae drivers.
10:00 AM - 22 Apr 2018
 
Twitter
David Bentley-Miller
@DBentleyMiller
Got stuck behind an idiot driver this morning with chocolate sauce and nuts all over his roof. Bloody Sundae drivers…....(I’m truly sorry )
4:12 AM - 12 May 2018
 
Reddit—Jokes
What is a slow moving ice cream truck called?
submitted June 18, 2018 by jessi83
A sundae driver.