[茶 Tea]

Snip

the term comes from the sounds the whips made when cracked against the skin of enslaved individuals, the slave masters were referred to by many slang terms and "cracker" is one of those terms, again because of the sounds the whips made when used against enslaved individuals. personally, i dont consider it to be derogatory 

By this logic doesn’t that make it an even shittier thing to call someone?

it's mean, sure, which is why i wouldn't say it in an elementary school. but being mean on the internet does not rise to the level of a community-wide issue requiring multiple days' worth of discussion.