You might want to look at what food you feed- foods with lots of dyes in them (the bright red and orange kibble pieces) upset a lot of cats' stomachs- same thing with treats. Puking from hairballs is generally a formed hair 'turd' for lack of a better term. Just because there was hair in it does not mean the hair caused the cat to vomit. Of course, the cat could have just ate too much, too fast, or didn't chew well. Worms can also cause vomiting.