Although not directly applicable, I have a Maserati indoor cover which I lay over the top of the car, partly because my garage is too small to allow access all round the car, but also to avoid the cover from pressing down on the bodywork to avoid the risk of scratching. Although I don't always use it, I happened to put it on yesterday as I had just polished and waxed the car and don't intend using it for a few weeks.
Even though it's garaged, the car still gets covered in dust (probably as a result of the gravel driveway outside), and as I use the car fairly infrequently it does have its benefits.
On another subject, if your leaving the car standing for periods of time and although perhaps stating the obvious, if possible I would strongly recommend a battery maintainer, I use a Ctek, as it avoids all sorts of electrical gremlins. Whilst I find I can leave my car for a few weeks without being charged, when I drive it things like the external temperature display becomes sluggish, and even the power amp (I have the B&W system, so maybe unique to that) can completely stop working - no phone, parking beepers, sat have voice, and obviously stereo, unless I reset by disconnecting the battery, also and I'm probably the only person who specced it the prehistoric WiFi hub plays up!