[jazzyjackson]

I reckon there's an implied sarcasm of "As If", that is: "as if I could care any less"

[sundarurfriend]

This is going to be my headcanon for why people do this (though it's more likely laziness/carelessness). This usage seems to be becoming more and more common, so this will help me pretend it makes sense and move on.

[dllthomas]

I like "I could care less. [In theory.]"