We used to cover ours with a sheet, then too got worried about static. Keep your shop area cleaner, hard to do but is a must around printers. We wipe our printers down with a swiffer every morning and before we leave a night.
I like to use a silk down comforter. No chance of static and it feels really good. Your printer will actually print better and love you for it. Go the extra distance and give it a weekly massage and you won't believe the difference in print quality.