Or the namer just couldn’t spell.
I used to have cats named Sally Ride and Nancy Drew.
Now my cat Finn is named after Phineas T. Freak (one of the Fabulous Furry Freak Brothers). Joining the household soon will be Thelma and Louise.
The other two current cats - Zoey and Dmitri - are not named after anyone famous, real or fictional.
My new kittens are Merry and Pippin. Well, Merry is really meringue, because he’s mostly white with some dark markings, like my chocolate chip meringue cookies.
Props for the Hobbit-hero names!
We once had a cat named Atticus, which my boys thought would be a good name for a lawyer’s cat. He was a pretty nice gray-brown tabby.
When I met my wife she had Billie and Igor, named after Holliday and Stravinksky. Later we had Jimi, and Loubee (named after Lou Rawls). Oreo is named after a famous cookie, and Cobie is named after Kurt Cobain.
We adopted two ginger tabby kittens (a pair of brothers) four years ago, and that’s what we named ours, too!
My brother Dick had a hyperactive tall thin black dog named Spider Washington, who was likely half greyhound and half space alien. Dick would tell anyone that Spider was named after a famous jazz piano player, with involved backstory - all of which he made up.
Does it count if the famous person is from ancient Greece ?
I had a cat nicknamed Eddie.
But his real name was Oedipus**
Because he …loved his mother. (Till I got him spayed)
** that’s a combo of Eddie, the pussy-cat.
Get it? Huh? Well, didya get it? Isn’t it brilliant?
I’ll be here all night…tip your waitress.
Both of our cats are rescues / adoptees, so they came with names, and the cat-mom refused point blank to rename them. One is Coco (short for Coco Chanel) - the other is Kai.
The first doesn’t need an explanation, the second, I always chose to call Kai, Last of the Brunnen-C. For anyone who is a Lexx fan, no, he isn’t black, and his singing voice is far inferior to the original.
As a kid, we gave some of our cats middle names of presidents. I know we had a Fitzgerald and a Milhouse.
My folks last cat was officially named Zuzu, after the kid in “it’s a Wonderful Life”, but mostly she was called “kitty!.” Yes, the exclamation point was part of the name.
We have a cat named Casimir, after General Pulaski.
Not many people outside of Chicago know the name these days, but he was famous enough to have some statues and holidays.
Our lab Sammy’s full name was Samwise Gamgee, used only on formal occasions. God, he was a good dog.
We have Adrian and Ambrose, two quite neurotic cats named for the Monk tv show brothers. We thought they were shy at the shelter, but turned out to be non-socialized nearly feral critters. 15 years later, we can pet them now - most of the time. Ambrose still will creep by me keeping an eye out in case I turn into a cat eating monster.
There’s Jack, and when my spouse awakes he can remind me where it’s from, he named him. Music?
A few years ago we lost Titus.
Titus Moody. A grand Maine coon, named for a character on the Fred Allen radio show, who was actor Parker Fennelly, the Pepperidge Farm spokesperson with the New England accent. He did the same voice on Fred Allen.
My cat is Ziva, after the character on NCIS. Our pug is Higgs after Dr. Peter Higgs, of Higgs Boson fame. Our late cat was Taz after the Tazmanian Devil of cartoon fame.
We often change the names of adopted cats, especially if they are kittens when we get them. This issue came with names i didn’t like. The old lady is named Rachel because her prior owner named her Racheal, though. (No, not Rachael, we would probably have kept that. As it’s, we decided to simplify the spelling.)
Ours are black and white, so we’ll be able to tell them apart. 
In 1980 we had a kitten that hadn’t been named yet. A Yankees baseball game was on the TV. The kitten saw the ball on the screen and tried to play with it. My sister joked that maybe it was a reincarnated baseball player. It came to me that Thurman Munson was the the catcher for the Yankees and died a few months earlier.
We named the kitten Thurman.
I named my first cat Dinah, after the cat in Alice in Wonderland. My second cat I named Verdi.
Our current cats are Gracie and Widget, so not named for the famous.
My late DH got a dog when he was in fourth grade and called him Sam but his name was really Samuel de Champlain. Sam never understood that he was a dog; he was very smart and thought he was DH’s furry little brother.