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Lots of cats go crazy for olives!
I once had a cat whose first encounter with green olives consisted of her detecting the scent fhrought a UNOPENED jar!
I’ve had a cat that would try to burrow through the blankets to get at the Ben-Gay I’d slathered on my back before going to bed. She acted just as whacked out as she did on a catnip high.
A couple of the current feline residents don’t get high on olives but will eat them if given the opportunity.
Cats are just weird, that’s all there is to it.
My cat Mr. Pants goes absolutely INSANE for olives! Not only does it provoke her to act super goofy (drooling, rubbing an olive all over herself elaborately), she does not get crazy from cat nip, or rather she might get a buzz but not act out in any way even close to how she does with an olive.
Mr Pants is a pretty serious stone cold killer cat. Her idea of play involves bloodshed. She has eaten many odd things (she loves strawberry donuts, go figure). Nothing provokes her like an olive though…
Is it Cat Week on Straight Dope?
It’s alllllways cat week on the Straight Dope.
I was wondering that myself
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…you have a female cat named Mr. Pants?
Hmm. Going to have to go home and break out the olives to see what happens.
Of course, all of mine are garlic stuffed. Wonder if that will make a difference.
Yes I have a female cat named Mr Pants. She don’t know her name, nor cares too, so it makes little difference. 
Furface loved his catnip - to the point of licking my fingers after I filled his favorite toy. But the attraction seemed to be short lived. 10 minutes or so and then he would walk away and ignore it for a couple of days.
His attraction to olives was puzzling. He liked to rub his face in the olive, even rolling it across the kitchen. But only certain brands; other brands, he would sniff and walk away.
Of course it will. A cat stuffed with garlic is too full to eat an olive.
I’m gonna go ahead and give that a thumbs up.
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QFT.
Batcat covets canned tomatoes, Incerta does the doggish roll-over-and-pee-submissively thing for a nibble of lemon.
Either may rouse themselves for tuna or 'nip, or not, depending on the phase of the moon, their mood, who lost the last game of kitty-poker, whether it is an alternate Tuesday, or a whim.
Cats is weird.
I have to say we’ve never owned a cat that showed the slightest interest in catnip, at any time. I was putting the whole thing down to a myth or, perhaps those stuffed mouses were filled with ersatz catnip. Never thought of olives, though.
Our cat Peach loved olives, but only as a toy. She would pounce on one and bat it around until it eventually became lodged under the fridge or somewhere. She wasn’t interested in eating them, though.
Olive juice would reduce my friend Jane’s cat to a writhing drooling Frenzy… IIRC, catnup had no effect on him…
We tried a catnip spray on the blanket one of our cats slept on, he turned his nose right up at. Instead he slept (a la lolcats monorail) on the very edge of his basket, perilously balanced above the odour of catnip.
I’ve had a couple cats who went catnip-like crazy for green olives. Rub, chew, drool, roll over on them.