Hope you will come to realize that running a cat is part of your personal responsibility for mitigating pollution from burning fossil fuel.

All of our trucks burn gas, all contribute to bad air locally and global warming generally. We ought to at least meet the letter of the law when it comes to emissions.

You can probably get away without runnning a cat, especially if you live in a rural area. And many here probably don't care that you do. But you may want to consider that not everyone thinks running without a cat is "cool". Besides that it is illegal.