There can be many reasons (house not being yours, etc.) but one of them could easily be cultural inertia.

During the first half of my life, very few people in my country (Italy) had AC in their homes. It wasn't until the recent high temperatures, which only became obvious 20 years ago or such, that everybody started installing them.

I can't find a historic chart specific to my country, but I suppose it wouldn't be too dissimilar from this:

https://www.telesurtv.net/export/sites/telesur/img/news/2017...