Every time someone says "I could care less" I want to scream into a pillow.
I had a theatre professor for three years who would always say that in spite of being a hardass on proper pronunciation and grammar in every other instance.
It's kind of interesting to see how certain idioms have been bastardized over the years to push a more oppressive, mother-knows-best boilerplate "wisdom" than what the original expressions suggested.
"A jack of all trades, master of none" originally follows up with "is better than a master of one." It just means it's preferable to be a well-rounded individual rather than someone who only specializes in one thing. It's ok to be good at everything and not be the best in one of them because you're far more versatile.
Also, "curiosity killed the cat" - "but satisfaction brought it back."
Edit: I'll translate the cake phrase into something GAF will understand.
"You can't have your unopened limited Collector's Edition video game and play it too."
But most of you buy two copies anyway so idk.