I'm a bit OCD when it comes to keeping my car clean and well protected, including applying wheel sealant and wax to the wheels. This hasn't stopped 2 of the unmarked diamond cut Charleston alloys on my mk6 GTD succumbing to whiteworm in the last couple of months.
They're being replaced under warranty this Friday. I'll be inspecting them carefully before I leave the dealership, to make sure they've not been damaged when the tyres are re-fitted!
I usually keep my cars 4.5 - 5 years, so I'm contemplating getting a set of more durable wheels; either a set of BBS CK's or anthracite VW motorsport wheels. I'd store the Charleston's and re-fit them when I sell the car to return it to OEM, and either fit the BBS's (or VW motorsports) to the GTD's replacement, or sell them, if they won't fit.