I'm not liking discount tire anymore either. I have a friend and a couple of her tires were losing air over a couple of days. Now this woman is cool, she's borrowed tools to work on her car , doing her own brakes and such and returns them fast and clean, knows how to weld, pretty knowledgeable.
She took her car to discount tire since that is where she got her tires to see if there was a leak. The shop said that its not the tires, there is some corrosion on the rims and she needs 4 new wheels. I am like wtf, and have her go to my local shop that proceeds to pull the tire, clean the wheel, remount, and the tires havent leaked a pound in 2 weeks.
Cleaning the the corrosion off the bead should be a standard step before mounting and balancing new tires.