This is something called an analogy. In particular I chose a "car analogy", which is a common technique. Sometimes when a non car analogy is used people smirkingly ask for or make up a car analogy even.

I could use a different one that would stir up much more controversial debate. What if stealing office supplies carried the death sentence? If you are guaranteed never to be caught how much of a deterrent would it be? If you get caught 100% of the time for that but all they do is to make you pay 10x what the supplies were worth?

Basically what I was trying to show that it's all about a combination of percentage of getting caught and the sentence. Only upping the possible sentence does not act as the deterrent people commonly attribute to it.