Checking out the GMC lot, I noticed many of the new Sierra's come with "chrome-clad aluminum wheels" which looked like a steel wheel (based on where the rim meets the tire) with a Chrome-plated plastic cover. The 17"s are still cast aluminum, but all the 18s seem to have these plastic wheels.

What's the buyer advantage?

Dodge, sry... Ram's half-ton 20" "chrome" wheel is the same way. It's a city boy's truck wheel design, for sure. Go to buy a replacement, you'll think you're paying for the real thing.

I have a set of older Ford chrome-clad rims, but they're chromed steel over steel rims. Not sure what the thinking was there, either.

Odd....

GM and Dodge use the "stainless hubcap crimped to steel rim" style, too. I had them on my '02 Silvy, they're still available on the GMT900.

Cheesey

If I'm not mistaken, GM started this trend with the 1999 Pontiac Grand Am. I leased a '99 Grand Am GT1 Sedan with the chrome-clad aluminum rims while I was working at a Buick, Pontiac, GMC dealership. The used car sales manager showed me one day in the showroom how the "chrome" was basically a plastic cover over top the aluminum rim. He said GM must be testing this out for use on other vehicles... this was almost 12 years ago!!