Because they chew balls.
The dog responds, "I've had a ruff day."
The license number of the car that hit him.
You have to chew before you swallow!
I must throw that doggie out the window !"!
Gluk gluk gluk (say it out loud)
One costs a lot of money to maintain, keep running, and give you the results you want. The other has four wheels.
Bugs Bunny.
No gain no pain.
Anatole me you're a pain in the neck !