Talk about a heat wave and strange housing. Houses in Texas have no basement which is bad enough in the summertime. California houses are even more ridiculous in the negative sense. Not only do they have no basement, they also have NO AIRCONS.
It isn't THAT ridiculous. We have no basement here in our house in AZ. Reason for that in general is that everything is built on pretty solid rock, . It would cost too much to dig a basement, and also, they are fairly useless here--i.e, no tornadoes..no need to have a cellar.
Northern CA has a different kind of climate--very much doubt they need air conditioning. But you are right...a few of the hotels I stayed at in San Fran did not have air conditioners at all. Just heaters.
In the Northeast we need everything - heat, insulation, air conditioning, swimming pools, basements, garages, whatever else offers some kind of relief/protection from the weather. The good thing, I guess, is that we're often spared a lot of the worst weather (although some of it feels pretty much like "worst" to me). Early Spring may "win the prize", when we can get ice storms one week and have major flooding and melting the next. (Forget I said that. Winter "wins the prize". )