#1. Yes. It's a thermonuclear astrophysical material reaction between your epidermis and the glossy paper stock. Have you ever put the AC on in your car, when it's warm outside, but raining? There's a residual reaction from the chemical exposure to your windshield. Same concept between the human body's operational temperature colliding with the 'room temperature' of your comic book.
#2. Also, yes. Comic books are meant to be handled. Sterile, sweaty hands, are better than 'question mark' hands that may contain bacteria or other infernal microscopic creatures looking to destroy the integrity of your Bubble Boy comic books.