What really grinds my gears is when people use the words "couple" and "few" in exactly the opposite way they are supposed to be used. How can a couple not be ex

What really grinds my gears is when people use the words "couple" and "few" in exactly the opposite way they are supposed to be used. How can a couple not be exactly two? Why would you then use few to mean exactly two? These people are almost always American. At least, I've never encountered someone I know not to be American making this error. It's part of a wider pattern I've noticed where Americans just say things backwards. Some examples include "let's see if I can't" (meaning let's see if I can), "could care less" (meaning couldn't care less), "me either" (meaning me neither), "irregardlees" (meaning regardless). It's an interesting phenomenon.