I wear glasses and definitely notice some of this. Especially if the juice is a higher VG juice. Then when that stuff sticks and you try and clean it, it smears more than actually being removed.
Go to the grocery store and pick up some glasses lens cleaner. You can get spray and a microfiber cloth or your can get wipes kind of like wet ones that are meant for glasses. They work like a dream. Mysterious, but like clockwork.
I second this. You just have to clean them a lot. Good microfiber cloth makes all the difference.