(A) soccer is a British term for the game and (B) it predates football as a term for soccer specifically because “football” originally referred to any game played on foot (as opposed to on horseback), and so it included rugby and other sports. Soccer was called “association football” after the clubs were formed, and rugby was “rugby football.” But it became popular in common slang at the time to tack an -er onto the end of things, so Rugby football became Rugger and Association Football became Assoccer, and then shortly after that, just soccer.

Watch some newsreels from British pro “football” in the 20s and 30s. Guess what they’re calling the sport EVERY SINGLE TIME? “Soccer.”

TL;DR: Soccer is a more precise and arguably more authentic and British term for the sport than football, so when you suggest Americans have no reason to call it that, you sound like an idiot.

And these people may prefer watching their own corrupt leagues, instead of the Americans’ corrupt league.