coarse ornamental grasses?.. why does my cat

My cat always eats the neighbours' coarse ornamental grasses which are thick and tough. It causes him (cat) to vomit.
I was wondering why he eats it.. he has cat grass at home.

Cats are actually drawn to grass because it helps them throw up and rid their stomaches of undigested material.  Some may eat grass, simply because they like the taste.  I've long suspected that some cats also are drawn to leaves with a narrow, strap-like shape - several of my cats have nibbled on any plant around with that shape.  Does your cat actually prefer the ornamental grass to his cat grass?  Or does he eat both?  

Just a warning about ornamental grasses:  some species are toxic to cats..  If you don't know what kind of ornamental grasses your neighbor has, ask, and check them on the ASPCA list of poisonous plants:  https://www.aspca.org/pet-care/animal-poison-control/cats-plant-list

he always vomits the whole thick blade of grass about an inch long.. it never makes it to digestion. It seems he likes the coarse stuff?
I'm not sure what variety my neighbour has but it looks like zebra grass. It grows very high in summer.

...removed all my landscape grasses from balcony since the cat will nibble on it.
I sternly tell the cat, "NO" when he approached the plant.. but can't see everything he does on the next side.
This is a condo bldg on the 3rd flow.
My cat likes to catch small birds and insects in suite next dr.
Elderly neighbour is ok with my cat playing there. It is a beautiful L-shaped balcony with gazebo so you know how cats like to climb small trees etc.. and those ornamental grasses are like a border. That means they are bushy and lots of them growing in summer months.

I remember reading once that cats do eat grass in order to vomit; like Margd mentioned above.  I wish i could remember where I read that.  It may have been in a magazine. 

It's pretty much common knowledge. Dogs do the same thing.

Also, I think some cats just want some greens; my Pretzel used to snack on the leaves of my miniature roses. Plus which, those long, ornamental grasses look a heck of a lot like cat toys. And when you "kill" your prey (grass in this case), what do you do with it? You eat it, of course!

Margret