all over glosses literally can be used all over. glossy eye looks, highlighters on cheeks, cheek color, lips, etc. still, i have a couple and don't really use them. ever. lol.
and glitz glosses...i'm pretty sure de-potting them would be a bad idea. i know some people HAVE de-potted cream products, but i just can't think of any reason why it would be worth the risk. i don't think they're the same size as blush pans, and obviously they wouldn't fit in eyeshadow palettes. i had a couple and hated them, so i returned them, but their packaging was not amongst my complaints. i thought the packaging was actually pretty convenient. i don't think you'd be doing yourself any great service by de-potting them.