I’ve been watching a few episodes of Caroline in the City, recently uploaded to youtube. In the show Caroline is a cartoonist with a daily strip, and occasional greeting card designs. Richard has one job, to colour her strips in*. This is portrayed as a full time job, and although the nature of his work attracts snark from other characters, the underlying show seems to support the idea that this is something that would take a fulltime work week. What’s the reality, is the Caroline/Richard working relationship an accurate portrayal of how it is really, or at least was iin the 90s?
*In one episode I saw, Caroline is talking about her strip, and says something like “and on Sundays they’re in colour” which implies Richard is only needed for 1 strip a week, but you can ignore or accept this line as you wish.
I believe most comic strips are colored in bulk in South Korean sweatshops.
Many comic strip artists at one time employed inkers, letterers, and background people to finish their work. I’m sure this has changed a lot with the advent of computers.
If I understand correctly, the thing about coloring back in the day was that it wasn’t the original drawings that were filled in but photostats of them. In other words, the drawings went out and you’d have to wait for the stats to come back so they could be colored in. So you would probably need someone to do that exclusively while you concentrated on other aspects of the process.
Even if it was only Sunday comics that were colored, they would have to be done weeks in advance, so the painter might get several Sunday strips to do all at once. Prior to photoreduction, they would also have been considerably larger than when you actually saw them in print. So yeah, I can see someone being employed full time to deal with this.
Makes you wonder how many creators actually worked on their strips at all once they were established. Charles Schulz, I believe, did all his own drawing and lettering with Peanuts. I’m pretty sure Hal Foster did all of his own pencil and inkwork in Prince Valiant.
Jim Davis, on the other hand, has apparently had pretty limited involvement in the actual production of Garfield strips for years, now.
Was there ever any indication the comic strip was merchandised onto posters and coffee mugs and toys and junk?
Comic strips today are colored digitally, almost always offshore. There are often issues where a character is talking about someone else’s “blue sweater” but it’s colored red. The colorists often are in Spanish or Korean speaking countries and cannot read the strips, and guess at what color everything should be from the images alone.
Nearly every daily strip is colored for online publication, even though very few print newspapers run weekday strips in color.
Assuming a 1990s sitcom portrayed a wholly pre-digital production process, and that daily strips were being colored for the rare papers that ran them that way, it’s still not realistic to employ someone just as a colorist. People in the comic book industry do a full page a day minimum as colorists. You wouldn’t need someone to do a three-panel strip and nothing else. Assuming the answer isn’t just “because it’s a sitcom and they didn’t need to explain it” he would most likely be the background artist, inker, and letterer too, or work a few hours a day on color and spend the rest helping with marketing etc.
As I remember, yes, the comic strip in Caroline in the City was merchandised to death. (And I’m so sorry I’ve got brain cells wasted on remembering that show.)
Greeting cards, and I recall a cereal named “Sweet Carolines” that had an unfortunate resemblance to a female body part.
Since I know absolutely nothing about the process; Is there anything serious about your post? 
So what do cartoonists do? Turn in the equivalent of an MS Word document of dialog; and let some 3rd party place previously drawn character drawings into a 3 strip panel?
I only saw two or three episodes of Caroline, but this thread reminded me of another show almost 50 years ago:
Hire ghost writers and artists, most likely. 
All of it. Well, “sweat shops” is probably hyperbole. But coloring in comic strips and most animated TV shows is outsourced to foreign countries. This is why Smithers was black in the first season of the Simpsons. The character had been intended as a white guy from the get-go, but when the episodes came back, he was mysteriously ethnic all of a sudden.
Most cartoonists write and draw their own material, and earn not very much money for it. Garfield is an outlier. AIUI, Jim Davis basically works as an editor for his own creation, approving ideas and tweaking individual strips that are written and drawn by his employees.
Using the Washington Post comics page as an example of what’s being published today: Garfield is ghost-created entirely while Jim Davis oversees a merchandise empire, Doonesbury is drawn by someone else who isn’t credited but Garry Trudeau still writes it. All the other strips on the page that still run new material (as opposed to “legacy” strips which are in print solely in reruns, e.g. Peanuts) are written and drawn by either the actual people credited, or members of their immediate family. Longer-tenured strips certainly have uncredited assistants doing backgrounds and lettering, and colorists are never credited on the comic strip page despite being listed in monthly comic books since the 70s.
A lot of “brand-name” soap opera strips change writing and pencilling personnel every few years, with credits adjusted accordingly. It’s a much bigger deal and more unusual for a humor strip to survive its creator.
I always thought that was because Smithers spent a lot of time on the beach at Fire Island. Or wanted to.