Why only recall cars in warm weather states? Just because the car was sold in NY or somewhere else, that person might be living in FL or AZ now.
They are trying to avoid making it a nationwide recall with a big press stink. My guess is that the hoses have aged faster in the South due to the heat, but the ones up North aren’t going to be terribly far behind. And those cars sold better up in Unionville than they did down here.
Temperatures only aggravate the process, but you are correct in your point. Look at the bright side, if their car explodes before they get here to cast their second or third vote in Florida . . . . .
On the reality point of your question, since it is GM, I’m sure the regulators worked out a deal to mitigate the exposure of costs to repair.