MegF.
That's for sale???
80 degrees is on the low side of the warm end so yours shouldn't be burning more than anyone elses'. I keep my cages at 82 (my snake room maintains an air temp of 77-80) and my snakes are out day and night for the most part. They are fed every 2 weeks or so and none are thin. It's much warmer out here where the snakes are found normally in the wild and they most likely are not eating weekly yet whatever I find is usually in excellent condition. Feeding every 3 days just because the animal is out and about is no reason to feed. I doubt they would lose weight if you didn't feed every 3 days. I don't even have a temp drop at night and mine still don't lose weight. Mine are also ravenous feeders due to only being fed twice a month. Snakes are opportunistic feeders and will start looking for food long before they need it, mostly because it usually (in the wild) would take a while to find and catch it. They can't afford to wait until they are starving to hunt, they expend a lot of energy and calories just looking for food...yet they aren't thin.