When you dislike someone so much that anything they do, no matter how minor or inoffensive, annoys you beyond any rational level - exemplified by the sentence "look at that bitch eating crackers like she owns the place".
A bitch eating crackers is someone (male or female(but usually female)) who no matter what they do like eating crackers pisses you off. Usually has a low IQ or intelligence. Other versions of the phrase include Bitch eating chicken.
I don't buy the schmegegge about Morty sleeping with Moira.
His version of the story was pure schmegegge.
The whole schmegegge was made up to get Liz a little bit of attention.
Looking or experiencing something nice after witnessing something horrid like a disgusting gif or a disturbing video. Typically used as eye bleach are nice images of whatever makes the disturbed person happy.