Took me a minute of googling to be vaguely sure you meant what I think you mean: the comma marking the end of your dependant interjectory clause there?

at least in America**,**

If so: I have no idea what you are talking about, that's drilled into us in school. Maybe people get lazy on the Internet but it is part of the rules and gets taught and used here

If I've misunderstood: what are you talking about, then?

I’m a comma-crazed Burgerstani, and I use those as well as the serial comma.

Ending a case that electrified punctuation pedants, grammar goons and comma connoisseurs, Oakhurst Dairy settled an overtime dispute with its drivers that hinged entirely on the lack of an Oxford comma in state law.

Oxford Comma Dispute Is Settled as Maine Drivers Get $5 Million

TIL.

For it. Its lack of use in a union contract was a factor in a court ruling some years back. That's when it went from pedantry to real-world consequence for me. Something was ruled similar to A and B rather than A or B.