If you can find it, the best stuff is industrial Viking degreaser or oven cleaner, undiluted. It's what we use in restaurants, because a tiny amount will dissolve even the toughest grease with minimal scrubbing. It's toxic and corrosive (it'll do to skin what it does to grease), so use it carefully and rinse very well, but the stuff is magic.
Positively magic -- spray a little on and then use a pot sprayer and the grease and grime just rinses off. I swear they suck the souls from babies to power the black magic contained in those bottles.
Failing that, a prolonged soak in boiling hot water with a ton of concentrated dish soap will loosen grease. "Magic eraser" scrubbing blocks work wonders for scrubbing off grease too, and take less elbow grease than the other scouring things.
Note: degreaser is not for normal use on pots and pans, just for hard to clean greasy buildup, such as you see on ovens, stovetops, and friers.
Best Answer
Clean rubber gloves can still leave marks. My guess is that the finger pads are more wornout (at microscopic level) and you've reached the not so smooth 'meat' part of the rubber that will stick and rub off on things.
Try with new gloves, or surgical latex gloves, or if marks on glass drive you nuts (like some of us), you can try microfiber gloves over rubber gloves.