Megatrep is right. I'm a metallurgical engineer, and the chrome-plated aluminum wheels are a real problem once corrosion begins. It doesn't take salt to make it start. I should probably check my electrochemistry chart again, but the dissimilar metals of chrome and aluminum set up a galvanic reaction. Aluminum, being less noble than chrome, will corrode sacrificially to the chrome. So, once corrosion starts, it's hard to stop it due to the galvanic process.
If the chrome completely covers the aluminum everywhere, at all times, it's OK, but once the coating is broken, it's a pain. I had the chrome-plated wheels on my '99 LHS, and I wouldn't want them again. The tires were always leaking around the bead (or valve stem) due to the corrosion buildup. With air in the tires, there's a fresh source of oxygen leaking out to enhance the corrosion. Short of the full recoating idea, you might be able to clean it up, spray it with a clear lacquer to protect the aluminum, use a bead sealer when the tires are mounted and have them filled with nitrogen. The nitrogen won't add to the corrosion because there won't be any oxygen available.
I haven't personally tried this, but scientifically, it could work. Hope that explains why these wheels can be such a problem. If anyone tries this fix, let me know if it works.