My two cats

[Hippykitty]

Are they indoor only cats? Maybe they need some grass. You can grow pots of cat-grass for them. Cats need fibre too, even if just to help with furballs. 

Or perhaps something in the salad smells like catnip? Or are they really after what you put on the salad, assuming that you're not veggie?

[Purdy Bear]

My father used to have a cat that went bonkers for cucumber and wouldn't leave them alone until he had some.   

[yecats]

My two cats are crazy every time I have a salad they go crazy and won't leave me alone till they get to eat off the plate and it only seems to be when I have salad never anything else they so weird lol but I love them