>>/88070/
That's a myth. We never really needed them but with weather getting hotter + for longer periods; a lot of people are getting them.

After we hit 40°C some years ago I decided to install AC too. 
I use it maybe a few weeks a year in the bedroom for sleeping (I would simply sleep downstairs in the past).
The main use case is when there's a long heatwave and the heat gets inside, which takes a while if you have triple layer solid brick walls.
This is why muricans need truly need AC, paper walls don't keep heat outside.