I'm sure all your cats do this so don't try and pretend otherwise 
I know they like to potter out and eat grass , then wander in, usyally where I'm sitting (so I get to clean it up ) and do that hunched up eurgh eurgh thing .
Projectile out a stream of foamy spit and a few blades of grass .
No fur balls (yet)
My DS said " They do that a lot"
But I don't think it's a that much. How often is too often?
(There's no blood , very rarely food , and always done in a place which will be noticed for effect ...like on our bed . DH side luckily )