Corrosion/Chrome lifting on OEM wheel bead

Over the past couple of months, I've been having a really slow leak on one of my tires. Has been worse lately as the weather has been colder. The tires have about 12,000 miles or so on them. I went to my local Discount Tire, (really like the guys,) for rotation and balance, and for two visits they couldn't find a leak. For the third visit (today,) I contacted the store manager in advance, and he offered to replace the tire free of charge.

When they dismounted the tire, the store manager showed me what is pictured....corrosion and also what appears to be the chrome lifting off the tire bead contact surface of the wheel. There was also "transfer" on the tire bead as well. He said he sees this all the time, it's very common, and it was definitely causing the slow leak.

For now, he cleaned the bead seat of the wheel up a little bit, and applied a coat of bead sealant to help seal the tire. I'm sure the condition is similar on the other 3 wheels, which are the 22s shown in my "signature picture." The DT manager also said there is a company in Dallas that can machine/restore the bead a little bit to remove the corrosion and chrome and smooth out the sealing surface for about $175 a wheel.

Tomorrow I'm going to review my extended warranty to see if perhaps the wheels can be evaluated and deemed defective, but I'm not counting on that.