You are talking about a few dollars in trade for your partner's comfort. Worth it in my book. If you are constantly trying to save $10/month (i.e., a couple of degrees on the A/C at night) while your SO is uncomfortable you may be trying to save in the wrong place.
Honestly, really? Personally I find it completely screwed up and my partner would rightly boot me in the arse if I wanted to do something that stupid.
WHAT A COMPLETE WASTE OF MONEY!
We all survived perfectly well before AC became the norm, and while I also like AC when it's hot don't you think we're a tiny bit addicted if we want to turn it on and then use a blanket?!?! It's like needing the heating on in spring because you want to talk around in the house in a t-shirt. Honestly, just put something warmer on and don't be so bloody precious and decadent!
My husband prefers a very narrow range of temperatures to sleep and has some difficulty sleeping in general, so it can become a source of tension when it's either hot or cold. That being said, he cuts his own hair, walks a couple miles rather than take the bus, never buys electronic gadgets, etc. I've tried the adjustment argument on him, only for him to spend several nights in a row unable to sleep well, affecting his job performance, so I've kind of given up on this. He's still a great husband and I do want to keep him around :).
Oh, and we live in Chicago, too and wouldn't run the AC at 57, but we do find that temps at which we would normally open the windows instead of running the AC at night are affected by us living on a very noisy street corner across from a 24/7 restaurant and where teenagers skateboard on the sidewalks. We generally open the windows during the day, but we then get a weird gray dust that settles on our floors and turns our feet black after a day. We don't live in the best neighborhood, but at least our rent is less than half what it was in Lincoln Park, so I do feel somewhat ok running the AC more than we did there.