Remind them of what they have done the next time you have to cancel and say "we aren't paying".
People did it for eons until about 100 years ago. And then it was rare, it didn't become common in residential buildings until the 1950's. Things were built with passive cooling in mind, now they are airtight boxes so the heat can be moved outside which, if you think about it, makes it even hotter outside the house.
It was funny to read about the heat in England last year and people "discovering" that if they opened the windows at night, the cooler air could get in the house. Amazing that it hasn't gotten hot enough there over the centuries that it wasn't already common practice.
I grew up in So. Cal, we never had A/C. My sister still lives there, no A/C though she lives a few blocks from the ocean so it stays cooler than inland. When I moved here in '79 it was 115°F 3 days the week I left. Car had no A/C but the shade from semis worked well

And yes, I was always in their mirror and ALWAYS dropped back if they needed to pass someone and I got in front temporarily if someone needed to pass me.
She loves heat and has the A/C set to 72°F???
We got a mini-split installed in the living/dining room last fall and the A/C is set to 79°F. It hasn't gotten quite that hot in the house yet even when it was over 90°F outside (open those windows at night!) but the unit also reduces humidity which makes it feel cooler. The unit is primarily so we don't have to run the oil furnace as much in the winter. Summer "cooling" is a secondary benefit.