Besides state inspections, it is still possible (though unlikely -- I've never heard of it happening) to get in trouble for messing with or disabling emissions equipment. There are even federal laws saying you can't remove or disable emissions devices.
That doesn't stop people from hollowing out their cat, putting a pipe through it, and passing visual inspections...and apparently it doesn't stop someone from spraypainting a thermos to use as a false evap canister.