Years down the road you will only regret it if you don't resolve family mental illness issues earlier. My BIL tried this with his AC during a summer trip. Kept his house at 80 with a house full of extended family. Temps in Utah were 100+. We left to a hotel instead after I told him off at 7pm at night after dinner and family members literally dripping in sweat. We had it out pretty good that trip, but guess what, it fixed it and it got the rest of my wife's family on my side and we shamed him into stop being a cheap skate if you insist in hosting family.

And yes, you have some form of mental illness if you lie about shutting off Internet or are too cheap to run the AC when hosting extended family gatherings in your home.