We've been doing that in Houston for quite some time. Looks like California is behind the times. :-P
I think we started doing this in Dallas back in about '98 or '99.
I live just 22 miles from the center of Houston and all calls to Houston are long distance. Even the next town, only 5 miles away is long distance.
My relatives in the DC metro area have been doing that for a while, too. Forever between Maryland, DC, and Virginia, and for a couple years now to everyone else in the Virginia 'burbs.
Also, about ten years ago, there were several phone outages in Northern VA, where you could still call DC and MD, but not anyone else in Virginia. Then it was announced that local in-state calls would go through if one did use the area code.
Everywhere I have lived since then, anytime there are phone system problems, I try dialing the area code first with local numbers to see if I can find a circuit to get my call through thataway.
No kidding - how strange that they are just now doing this! Of course, we don't have to dial 1 unless it's long-distance; ours is just 10 digits. Honestly, I thought everybody had it now.