No it isn't.
Do you own a pizza cutter? And if you had to cut a pizza without a pizza cutter, how difficult a task would that be for you?
Yes, I have one: Not all take-aways around here cut their pizzas and it's a bit inconvenient to use a knife when cutting it, while it still is in
When I make my own pizzas, I'll usually just take what's already hanging right there in front of me on a magnetic rack: a knife.