You can drive without a catalytic converter (though you will fail smog test so it could eventually cascade to that).
So, yeah, you can drive a car without a cat, but not without a muffler (generally). Fix it tickets still incur a monetary cost.
This is incorrect for modern diesels that have a DPF system and inject DEF fluid. The cats are required hardware. You may be allowed 50-250 miles without them then the vehicle will not operate. It is well within possibility that someone stealing your cat between two places in Texas could be a big problem for you.