Emissions required in some states

[Ezflake]

Anyone know what GM adds to the vehicle with the states that require emissions vs the states that don’t on 6.2 engines or the vehicle it self? 

I saw this listed on one that was on a build dealer inventory list. Colorado Connecticut Delaware Maine, Maryland, Massachusetts, Minnesota, Nevada, New Jersey New York Oregon Pennsylvania Rhode Island Vermont Virginia, and Washington. But I was surprised California was not on the list. I keep vehicles for 15 to 20 years. I’m sure replacement parts after warranty is out are cheaper without emissions if there is part differences.  
I don’t know if it makes a difference whether it has it not, just kind of curious if there’s a drawback from ones that do have emissions

Thanks