Some nutritional value
One variety helps to reduce hair balls
Cons:
Cats love them
They pester me mercilessly for treats

Blacky and Inky have been pestering me for treats for over 15 years now. Tuffy the 2nd and Cassie are new to the game, since they are the young ones.
Whenever I leave the house, however briefly, they insist that I make up for their inconvenience by pawing out treats. Whenever my friend Catherine comes by, the kitty-cat dance begins again. You see, Catherine often picks up groceries for me, so the cats naturally assume that she is bringing treats for them.
Temptations are their favorite, although they will eat some other brands of cat treats. Whiskas claims that these treats have good nutritional value, but they cannot be the entire diet for the cats. Blacky and Inky disagree, and they would eat a whole bag of treats every day if I let them. I paw out three or four treats at a time.

Cats love them, and I like to make my cats happy.